I took James to the doctor today as a follow-up to his 4-month appointment where James' head circumference was suddenly in the 95th percentile. I'm happy to report that his head has not really grown that much in the last month (75th percentile now), and the doctor thinks everything looks good. Of course we'll still keep track in the coming months, but I'm glad I didn't worry about it too much.
Also, I was right about the growth spurt! James weighs 15 lbs 14 oz now! Four more ounces and he will have doubled his birth weight. :)