Luke's new word

Luke's been saying, "Mice! Mice!"

Huh? What? That can't be it.

I finally figured it out yesterday. He's saying, "My's! My's!"

As in "Mine!"

He hears "Luke's," "Daddy's," "Mommy's," "his," "hers," "yours." So why not "my's?"

(Of course, this means he's moving into the whole, "me-my-mine-mine-mine" stage, doesn't it? Uh oh. Parenting advice welcome!)