I'm really sort of looking for reassurance, I think. My ds is 8 months though was 4 weeks prem so always referred to by his corrected age. He's very good at wriggling around on the floor in circles but has no interest in sitting up (actually wriggles back onto his back) or standing (when I'm holding him) and zero interest in crawling. I keep being told he'll do it in his own time, I'm also told boys can be slower than girls to do these things. So, as I said before I'm looking for a bit of reassurance...what age were your dc doing these things and any suggestions to encourage him to sit, crawl, etc?