My eight month old is currently standing and playing a chair like a drum. Yes, my eight month old is standing, only when holding on, but standing none the less. For the past month and a half he had one mission, to be vertical. I am pretty sure he only learned to crawl, so he could get to objects to climb on. Both activities happened simultaneously at Christmas. He has been on the normal edge of early for all of his physical milestones, but so far pulling up seems to be his favorite.