Oh it sucks doesn't it. I had pain - worse and earlier - with 2nd bub too. Osteo helped with my other aches and pains but said that there was little she could do for my pelvis. Said it was up to me to keep pelvic floor and core muscles engaged as much as possible, to tuck in my tailbone and avoid inflaming it through wide-leg stances, squatting, too much walking etc. I wore a support belt from about 18 weeks and found this a lot of help. Also reminded to to restrict my movement.