Let her know that your heart is bigger because it’s older so you have more room for love.

I have peer-reviewed this paper and found it to be accurate.

I like how visually she thinks about it

Smart kid. She’s right.

I would not recommend arguing with a little kid, but I have to point out that capacity for feeling is something that can be developed, like a muscle. The more you use it, the bigger and stronger it gets. It can similarly atrophy if under-exercised, perhaps due to neglect or injury.