My DS2 had been alot slower at everything then DS1. DS2 only started crawling just before he was 10months old (DS1 was 7months), 1st roll over (back to tummy) was about 6months (DS1 was 3months), then 2nd way (tummy to back) was 7months (DS1 was 4 or 5 months), standing up about 11months (DS1 was 8months) and even though DS2 has begun this week to let go of things...I don't think he'll be walking by or even just after his 1st birthday (DS1 walked at 13months). Even teeth are slow...DS2 still only has his 2 bottom teeth (though top left is sooo close to breaking through...any day now). I always thought DS2 would've been super keen to do all these things with having a brother to watch and chase after, but obviously he is his own person and is just developing in his own time. Maybe he has been just happy to just sit/lay there and watch his 2.5 year old brother being a monkey

I'm not worried though, I know it'll happen eventually (its probably been a good thing as there is one less to chase after....especially out our doggy door ).