Head size increasing to rapidly?

Hello, just looking for some general info/feedback. My son just went in for his 6 month check up and I was told that his head is growing in appropriately for his size. He is a very large boy (was 11lbs 10oz at birth and is 22.5 lbs now) but his head is still growing much faster then the rest of his body. I am waiting for an appointment to see the pediatrician but in the mean time I was wondering if anyone else has experience with this and what the outcome was? Good or bad. As of now there has been no delays in development or issues that I have seen.