It was in a drama topic about family rp's, I think someone brought up how a user on his server asked if they could be the doge.
It's also an actual thing that I'm sure a number of people have seen done on FamilyRp servers.
Most people either want to be your child/baby or your dog/cat for some reason.
It's more annoying when you get it on non FamilyRp servers, like on city-buildRp servers, where someone comes along asks to be your child just so that they don't have to build their own house/building.