My DD who is now 15 never crawled. No matter how hard we tried to get her to crawl, she never did it. Eventually she just got up and walked. She was delayed on almost all her skills-talking, walking, etc. etc. etc. Not hugely late, but always late. The doctor told us she would be a "back of the pack" kind of kid. He was right. She gets special ed services and speech. She is a very challenging child and ALWAYS picks the hardest way to do anything and everything. I think if your child just skips crawling it is of little significance. If they skip crawling and are late on all the other milestones, it is a heads up that you need to be diligent in your follow up with the doctors. Early intervention is SO important. The doctors didn't listen to me-they said I was "overly concerned" because I was an older mom, I had "too much time on my hands" because I was a stay at home mom, etc. so she missed all the EI. When she got to kindergarten and the teacher made the recommendation for evaluation it was ALL different! One or two missed milestones are usually fine but if you see a pattern or if you just sense something is off, make a big deal out of it because you can never get back lost time.