Thanks for bringing this up! This is actually not a glitch. When I fixed up the happiness/hunger code, I intentionally made it so minions would only increase happiness up to 9. This is so it is still possible to play with toys with that pet.

This was long ago that I don't remember exactly, but I am pretty sure this was a requested QoL feature - people wanted minions to increase happiness to one point below max, so that they can still complete Major Drills quest that require playing with a toy.

If they were at 10/10 happiness before the minion was attached, that will never drop, so maybe that is what happened?

Because the code is just like

• Do not drop happiness for pets with minions
• For pets with happiness < 9, make them happier every hour if they have minions

So if a pet is at 10/10 happiness, it will not drop, so it'll never go down to 9.