Her Son Died at 13 Years Old After Transplant Complications. How Other Grieving Moms Are Helping Her Heal (Exclusive)

• Arivia Smith was a young mom who welcomed son Zack when she was a teen

• Zack was born with kidney disease, but the medical complications from it didn't start until he was almost 10

• At 13 years old, his family thought a kidney transplant would be the answer to their prayers, but a series of complications led to the young boy's death

Arivia Smith walked a tough road as a young mother.

Arivia was just 15 when she welcomed son Zack, raising him as a single mom with the support of her own mom. From the beginning, they learned Zack would have a complex health journey.

"I was only 15 years old when I was pregnant with Zack. They found that fluid was unable to come out of his bladder in utero, which caused chronic kidney disease. They advised me to terminate the pregnancy because they thought he wouldn't survive more than two hours after he was born," she tells PEOPLE. "I had to go to the hospital throughout every week of my pregnancy to see a nephrologist and my OB."

Despite the grim prognosis, Arivia welcomed Zack at 37 weeks with no complications.

"I got to hold him for 10 minutes before they took him to the NICU, where he stayed for a month. They had to put him on a special formula. It took multiple tries to figure out what would work for him. I could not breastfeed him because it was impacting his creatinine. We managed his medication, his electrolytes, his creatinine and went to the kidney doctor once a month."

The kidney issues also resulted in an additional health concern, Arivia explains. "His hips were out of place at birth so he had to have surgery at 8 months and wear a full body cast to help keep his hips in place for four months."

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Related: Woman, 20, Recalls 'Morbid' Kidney Disease Disrupting Her Life: 'I Couldn't Be a Normal Teenager' (Exclusive)

Despite those setbacks, Zack got to an enjoy a relatively normal childhood for his first 10 years, with his family and medical team's support.

"We didn't start seeing complications until he was around 10 years old, where his kidney function began failing. He had two big cysts on his right kidney and six cysts on his left kidney. None of them ever busted but as a result, his kidneys didn't grow with him," Arivia explains.

"As he was getting older and bigger, he was outgrowing his kidneys. We always knew he would need a kidney transplant, but starting to see those changes was really different for us. Before that, you wouldn't think he had chronic kidney disease."

The problems began presenting in concerning ways, but the family didn't think they'd require the lifestyle shift they later would.

"He was tired more often and having problems with eating. When he was 11, his doctor said that he would need to be put on dialysis. He was put on hemodialysis, but later he had to do peritoneal dialysis. So he did that when he was 11. He had to get a port in his stomach. We did the dialysis with him every night."

Getting dialysis was both physically and emotionally difficult for Zack, who "had this childhood and then all of a sudden, everything changed," as his mom says.

"He wasn't able to go anyone's house but his grandma because she was the only other person who knew how to set up his dialysis machine. He couldn't go sleep over a friend's house, and he was kind of embarrassed. We'd tell him there's nothing to be embarrassed about. I mean, we had so many talks between me and him and me and my husband, just trying to build his confidence back," Arivia says.

"He would feel tired and his stomach would hurt. He was upset he couldn't run around with his siblings. And then about two years into being on dialysis, we get the call for the kidney."

They'd learned early in Zack's life that a kidney transplant would eventually be necessary. "We were told this would be the thing that makes him better. We're telling Zack like, 'Once you get through this day, you're straight. Everything is going to be fine. You're going to be able to play basketball. You're going to be able to do the things you want to. You're going to have the energy to run around with your brother and your sister, your cousin, your friends.' "

Arivia says that today, her perspective is completely different. "We were blind to what would happen after. He was on the transplant list for maybe a month before we got the call that a kidney was available for him."

Arivia had wanted to donate a kidney to her son herself, but was pregnant at the time the need came up, making her ineligible to donate. "I would have had to wait until a year after I had the baby, so it wouldn't have worked out," she shares.

The call coming so soon after they joined the list felt like the answer they'd been waiting for. "We got the call and went to Charlotte, N.C., to do all the evaluations. Everything went well."

When it came time for the surgery the family was "nervous, of course, but it was something we were happy about."

"We celebrated and jumped for joy. He got the kidney transplant and all the updates were good. The kidney was added, but his others were not removed. It was working and everything was fine. Then maybe a few days after the transplant, Zack started having high blood pressure."

After medically raising it for the procedure, Zack's blood pressure wasn't regulating. Additionally, he was "in some pain and missing home after being in the hospital for a week," Arivia shares.

"They came to us and said they thought Zack's body was rejecting the kidney, but it was a mild rejection. They had to take all the plasma out of his body and put in new plasma to eliminate the antibodies that were trying to attack the kidney."

He continued treatment in the hospital as they sought to get him regulated. "That happened over a course of five days," Arivia recalls. "His immune system was struggling because they didn't want it so active that it would attack the organ. We were in the hospital a total of 30 days before we were able to go home."

The rest of the family was thrilled to have Zack home, particularly his siblings, who were 9, 6, 1 and 8 months at that time. The day after the family was reunited, they were spending time at home and debating a trip to IHOP when the unexpected happened.

"Zack took his medicine and went to take a shower while I laid down with the other kids. Then he came and laid down with all of us in the bed. Everyone fell asleep and when I woke up, Zack was seizing," she recalls.

"I had never seen someone have a seizure before, let alone my kid. I was freaking out. I woke my husband up and he tried to hold him in place. I couldn't find my phone and had to get his to call an ambulance. They came and determined he'd had a grand mal seizure."

Zack had another seizure on the way to the hospital, and was in the midst another when Arivia was taken to him at the hospital.

"They were even more aggressive. He was admitted, just over 12 hours after we got discharged from the further hospital for the kidney transplant," Arivia says.

Miraculously, Zack seemed okay after waking up from light sedation. "You'd think nothing happened to the kid. He was up and walking and talking. He did have some temporary vision loss when he first woke up. It turns out that because of his high blood pressure and the rejection medication he had to take for the kidney transplant, he overdosed on the rejection medication."

As a result of the incident, Zack developed a brain syndrome called posterior reversible encephalopathy syndrome (PRES). The syndrome is characterized by a headache, seizures, altered mental status and visual loss.

"He came home a week later with four more medications, taking a total of 18 pills a day," Arivia says.

The severe headaches resulting from PRES made it difficult for Zack to go to school most days. He also had a raspy cough that they first attributed to his breathing tube from surgery but ended up lingering afterwards. Amidst her son's battle, Arivia had to work to justify her son's absences to the school district.

"I was explaining the situation like my child didn't just go through something traumatic. The school was telling me he was supposed to be better after the kidney transplant, so he couldn't keep missing days. There were days he'd go to school and call me to pick him up in an hour or two."

When Zack called home one day with symptoms of a cold, his doctors initially told Arivia to treat it like a cold because "we didn't want to take him to the hospital unnecessarily and risk other infections."

Zack spiked a high fever, leaving both mom and son fearful of another hospitalization. "He was begging me, 'Mommy please no, I don't want to go to the hospital.' And I was like, 'Zack baby, I don't want to go either.' But we ultimately didn't have a choice."

The next morning, Zack didn't look well and was reluctant to get up. Arivia consulted with his doctors and they determined he needed to be seen at the hospital. She alerted the rest of the family to make sure her younger kids were cared for. Initially, they decided Arivia's mom would go with Zack, with Arivia meeting them after work.

"My mom called and said he let out this big gasp, like gasping for air, and she said, 'You probably need to come here because something is going on.' The lab results were terrible. By the time I got there, my baby couldn't breathe," she recalls.

"I'm not sure he even knew who I was. He was out of it. His oxygen was down to 65 and his pulse was low. Everything that was supposed to be high was low and everything that was supposed to be low was high."

Doctors informed Arivia that Zack had strep throat, pneumonia and RSV, and was in septic shock. All of his organs shut down from there.

"I begged the doctors to do everything they could to save him. I was lost and beside myself," Arivia says. "I really didn't understand what was going on. He had just had a kidney transplant. I didn't understand why this was happening."

"They were able to put him on ethanol dialysis, which they usually don't do for kids. They had to open up his chest, crack it open, to put valves directly into his heart to try to help his heart recover. He was transported back to the hospital where he got the kidney transplant."

"Seeing my son after all of that happened to him was absolutely horrifying. I had just seen this kid up and about hours ago and now he didn't look like himself. He was swollen, his eyes were bulging. I didn't know what I was going to walk into."

Arivia was shocked to hear doctors refer to her son as "the sickest child in North Carolina right now," something she'd hear multiple times throughout the grueling 32 days Zack was hospitalized.

"They told us every single day that they did not think Zack would survive. He fought for 32 days. They said if he had survived, Zack wouldn't have been the child we knew him to be before this happened. Me and my husband didn't care. We were ready to take everything that came with that. I think that's why every day they told us, 'You might want to consider letting him go to rest.' "

For the distraught mom, "it all happened so fast."

"We were resting at Ronald McDonald House when they told us to come back because he was declining fast. I was going to go alone and let my husband stay with the babies but they told us that we should both go and a nurse could help with the babies. And they'd never done that before, so I knew this was it."

Arivia remembers seeing her son and thinking that, "It was something that no one should have to see as far as their child or any of their loved ones going through."

"Me and my husband had to go back to the Ronald McDonald House and talk about it. And we both seen what we'd seen, and we both decided that this is probably enough. We had already had a meeting with his doctors or his care team the next day at 12 o'clock. So we decided to still go to that meeting where they told us what we already knew."

The family discussed what Zack would want and grappled with the fact it seemed they'd explored every option available.

"At the point they told us all they could do was comfort him, and considering what I saw the night before, I did not hesitate to say, 'We'll do this today,' " she says. "At that point, I didn't want him to suffer anymore. And at that point, my son was already gone."

Arivia's family members all made their way to the hospital to say their goodbyes to the 13-year-old.

"My kids were able to come in and say goodbye to their brother, which I struggled with. I didn't want them to have to go through that, but the doctor put it in perspective for me. It had traumatized me as a grown adult, but I did what I could. I put the eye mask on so they didn't have to see. He was under his Ninja Turtle blanket. They got to talk to him. I'm so happy that I did let them go in and say goodbye."

The siblings struggled immensely with their oldest brother's death.

"In the beginning, all I could do was hold them while they cried. I had no idea how to comfort them because I couldn't comfort myself, and my husband was in the same boat," Arivia says. "I put my kids in grief therapy for children to get them some help. And it's still challenging to this day."

"We have a memorial that has this box that says 'Letters for Zack,' where if one of us wants to say something to him, they can write it or draw it and put it in there. My husband and I don't read them because it's personal between Zack and his siblings. My daughter is very open and she's always drawing him a picture. When she leaves the house, she's always saying, 'Bye Zack, see you in a minute.' "

"I've been trying to give myself some grace. I'm trying to be understanding with myself that this hasn't been that long," Arivia says. "For me, it feels like it just happened and for everyone else, it's been months and months. So I'm trying to give myself some grace and feel what I need to feel."

"When I shared this story on TikTok, I had no idea it was going to go viral. It was just something I had to do. I used to share TikToks before all of this happened, with Zack's kidney transplant. My account ended up getting banned so I stopped until last December, when I decided to share Zack's story," she says.

"I got such an outpouring of love and support. It's very vulnerable so to share something so raw helped me a lot in my healing process. People are saying his name and sharing love and his memory. What he went through, all the pain he went through, it wasn't in vain. Once I felt that, it made me decide to keep going and keep sharing it," she says.

Arivia is grateful to have connected with a community of grieving people, especially grieving moms.

"I have met so many other grieving moms, so many other people I have educated about septic shock and transplants. The messages I get from grieving moms really connected me to a whole community out there," she continues. "You never think you'll find yourself in this position until you go through it. To have this big thing in common with so many strangers is heartbreaking, but at least we can connect and talk about our babies and other beloved people we lost."

Read the original article on People