My tummy is like a drum

This happened last week while 哥哥 was switching channels ...

哥哥 : 妈妈, see that (Slim Spa advertisement on tv)! That's the one I wanted to tell you.
妈妈 : Yes, what about that?
哥哥 : It helps your tummy become smaller.
妈妈 : Why? My tummy very big meh?
哥哥 : Hmm ... wait. I see .... (he then wrap both his arms around my waist and then gently taps on my tummy)
哥哥 : Yes, you need. See, your tummy like a drum. So big.
妈妈 : Grr ....

So very not adorable. LOL