In the sweet shot, big brother Jackson Kyle, 5, holds his baby sibling Josiah Luke, 3 months, upright for the picture and sweetly rests his cheek on Josiah's head. Tori and husband Zach Roloff share their two boys plus daughter Lilah Ray, 2.
In a second slide, Tori holds baby Josiah up to give him a kiss on the cheek.
"I mean....💙💙," she captioned the sweet set of snaps.
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"3 months!" Tori, 31, wrote in the caption of her post, alongside cute pictures of Josiah wearing a brown onesie with a pair of matching sandals.
"Josiah is finally sleeping! 💤 He is almost 13 pounds! 💪🏼," the mom of three continued. "Si is tracking and LOVES his brother! 👦🏻👦🏻 He loves being talked to! 🗣"
"Josiah doesn't give away smiles easily though! 🤩," she added. "Bath is still our favorite time! 🛁Love you sweet si si!!"
One snap featured within the post shows Josiah sitting on a couch next to a sign that reads "3 months old." Another shows an adorable close-up of his face with his tongue out.
The trio of pictures of her newborn was shared shortly after Tori posted family photos from Josiah's first beach trip.