The strongest argument against letting a young person ever have a pet is that, eventually, they’re likely to become emotionally attached to it, which’ll almost invariably become a problem once the pet in question decides to die.
Everyone knows that there’s a certain amount of risk involving emotional trauma whenever kids are given the chance to bond with animals, but of course, that doesn’t stop the Creed family in Kevin Kölsch and Dennis Widmyer’s Pet Sematary remake where the Creed actually has more than just pet problems.