I love (generally *ahem*) how the mimic each other.  For example, today at the store:

Emma:  Look at that daarling chair!

Gregory:  Look daarling tractor!

Although I’m forseeing some potential for trouble when the baby is born, as evidenced by this exchange.

Emma (cuddling on my lap):  I love my mommy.

Gregory (coming over and leaning into me):  My mommy!

Emma:  No, she’s my mommy too!

Gregory:  No, my mommy!  Gregory sit in mommy’s lap.  Push push (as he tries to push Emma out of my lap)

Emma (as I readjust and make room for them both, and pull Gregory into my lap):  See, she’s both of our mommy.

Gregory proceeds to cuddle into me and glares at Emma all the while.

Hmm…  this should be interesting.