"Mommy, Daddy called you my mother," Tuck said, incredulously.
"Well, that's because I am. I am your mother."
"No, you're not. You have to grow up a really lot to be a mother. You're still a mommy."
A fine distinction. I'm pretty sure he's the one who has to grow up 'a really lot' to think of me as his mother. I'm content with being a mommy for quite a long while, actually.