The Sinclair family start to think that Baby isn't their birth child when they remember an earth quake back before he was born, and they think two eggs may have been switched by accident during the earthquake. So, they decide to trade babies with the family that had the other egg that may have been their birth child. Well, it doesn't turn out so well, and they realise that you don't have to be blood to be family. They really start to miss Baby and want to take him back. Well, I think they did the right thing by taking him back into their home again, because Baby may not have been their biological son, but he was a part of their lives.
It was very emotional, and I cried when they gave up their baby. It was such a sweet episode.