4 months

 At four months Mr. Jack can roll from tummy to back, but more often from back to tummy.  Loves grabbing at toys and putting them in his mouth, along with as many fingers as he can.  He's a wild card at night for how many hours he'll sleep at a time, but sleeps very soundly when he his sleeping.  At his four month check-up he weighed 16.8 lbs, and measured 27.5 inches long!  That puts him in the 75 percentile for weight and the 99 percentile for height.  Go boy!  Oh...and LOTS of drool.