Well, Thomas had his 4 month check up today and here are his stats. . .
Length 25.5 inches (75th percentile)
Weight 13.11 (30th percentile)
Head 16 3/8ths (25th percentile)
He is a happy baby who is really enjoying rolling from his back to his stomach now. And this morning when I went to the bathroom, I came out a few minutes later to find that he was about two feet from where I had origionally had him on the floor. So it looks like I have a roller.