Aidan often gets his pronouns mixed up. Him's instead of his, him's instead of hers (he has gotten better with that one), her instead of she, you instead of I, etc. We always gently correct, try to get him to say it correctly at least once (sometimes more than that if he immediately lapses back). Well...here's an example from this morning.
Aidan says, "Daddy, Tessa and her mommy are home!"
Rob says, "Where's Elliot?"
"Him's at school." Aidan replied
Rob and I both say, "HE is at school."
"He is at school." Aidan replies.
Rob says: "Where's Gabby?"
"Her's at school" was Aidan's reply.
"SHE is at school." we say.
"He is at school." Aidan said.
"No, SHE is at school." Rob said and then went on to say, "Boys are he's and girls are she's."
"WHY?" Aidan asks.
"Good question buddy--but it's just the way our language works."