Where is Baby Lucas?

For a while now, Hudson has been pointing to Mommy's belly and saying "baby", referring to his baby brother, Luke. However, in the past couple days, Lucas has moved from Mommy's belly to Hudson's belly. Now when asked "Where's the baby?" or "Point to the baby.", Hudson will point to his own belly and say "baby". Although, Hudson does know what a baby is because, lately, when I've held a baby Hudson will point to the baby and say "Baby". So, I'm not sure if he thinks a baby and his belly are the same word or if he really thinks there's a baby inside his belly!