My Tummy's Full

Presley eats until her "tummy's full," but instead of just telling us that her tummy is full, she lifts up her shirt and shows us that "her tummy's full," and it does always appear to be full.  Last week one night after she had eaten 1.5 bowls of spaghetti and drank all of her juice, she let us know that she was finished because her "tummy's full.”  Here is what followed:
Me:  Presley, are you sure you’re finished?
P1:  Yes, daddy, my tummy's full. (Lifting up her shirt for a second time)
Me:  Okay.  Presley, can daddy eat the rest of your spaghetti?
P1:  Daddy! ! ! ! !   Your tummy is already full.
Me:  No it’s not.  I haven’t eaten yet.
P1:  Yes, it is.  I’ll show you.
P1 (after she walked over to me and lifted up my shirt): See Daddy, your tummy IS full.

I was sucking in as she lifted up my shirt, and I really hadn’t eaten yet, but apparently my tummy still appeared to be “full.”  I need to go on a diet.