help with my cat, 32 weeks old.? eating habits.?

Question

well ive been somewhere else for a day and then when i got home my cat was pissed off and wouldnt eat or drink.
she has also got quite fat recently but i find this only happens with short haiired cats?
my 2 long haired cats are thin as ever.
my short haired ones are quite fat.


anyone know why they get fatter or why she might be moody?