The LifeStraw is marked down to just $21.
Princess Anne clocked up the most engagements last year.
It comes after Harry said he and Meghan will have "two children, maximum," to save the planet.
The Duke of Cambridge has said it would be "absolutely fine by me" if George, Charlotte and Louis came out as gay or lesbian in future.
"If your husband’s called king, you’re called queen," says former BBC royal correspondent Jennie Bond.
The Duke and Duchess of Cambridge are 'deeply concerned' and 'saddened.'
Royal sources have said it never entered the prince's head to give up driving after the crash.