Sam has always been a string bean. He didn't get "fun" at all until he was closer to 4-5 months, and even then he was still pretty much a bump on a log. I think 5-6 months is when Sam started being more giggly, finding strange things funny (like coughing and feet) and liking to be tickled. I bet B will start smiling any day now, though. Hang in there!