DD is just over 8 months old and not moving yet. She rolls front to back (which she started doing at 12 weeks, did it for about a month, then stopped until she was 6 months old again). She won't roll back to front and is not at all on the move when it comes to crawling or pulling herself around.

She can however sit very well and I've been told a number of times that apparently her fine motor skills are great for her age (I guess that's a product to sitting and playing with toys lol). Anyway, should I be concerned about this lack if movement? It seems that everyone elses babies are on the go....