Names for Aidan

Charlie has a few very cutie names for Aidan. He started with Mr. Aidan and has moved to "the little one" and "the little guy". Charlie will say things like, "Mum where is the little one?" Or "Oh, I got the little guy" as we race to get Aidan who is climbing the stairs! He is very serious when he says it and seems like such a grown-up. He loves his little bro. No question about it. And Aidan love him.