Grandpa

Niece : 爷爷，做么你整天吃不饱的？ (Grandpa, why are you always hungry?)
Dad : ...
Niece : 你的肚子很大吗？(Is is because you have a big tummy?)
Dad : ... *eats*

Ahh kids will be kids. HAHAHAHAHAHAHA.

No, I don't think my dad's a big eater, at least for a middle-aged man, he isn't. Heh. He just happened to be eating whenever my niece's awake. And my niece always notices whoever that's eating in the kitchen.