For a long time Jacob called both Nate and Sam by Nate's name. But he called Nate, Nate-dog. And he called Sam, just plain Nate. I tried over and over to get him to say Sam but he wouldn't. One day a few weeks ago, Jacob was running around the house yelling "Yummy, Yummy" I asked him if he was hungry and he looked at me like I was crazy and kept running around and repeating it. Finally he finds Sam and runs up to him, points, and yells "Yummy" So I guess Yummy is better than calling him Nate. He's gotten to a point now that occasionally he says "Yammy" instead of "Yummy". Either way it's really cute.
On a side note, the other day Jason was talking to Jacob and said "you're trouble" and Jacob looks at him and points and says "Rubble!" Jason laughs and says "No, you're trouble" and Jacob points again and says "Daddy Rubble!!!" Then he looks at me and says "Mommy Rubble!" Not sure how I got dragged into it! But now he's doing it to his brothers everytime they do something he doesn't like.