My DS is 8 months old and trying to dress him or change his nappy is a real battle. He always rolls onto his front and tries to crawl away when I try to dress him or change his nappy. If I try and keep him still he just starts crying which, if I don't let go of him turns into full-on screaming. It's so hard to do up the many poppers on a sleep suit when he's rolling over constantly. I've tried dressing him once he's rolled over but he just tries to crawl away. Standing him up doesn't help as it upsets him too. I've tried toys etc. to distract him but that only ever works for about 10 seconds. Is this normal and just one of the many 'phases'?