My first little boy walked around the 18mth mark, he actually never traditionally crawled. He only commando crawled and when he would try and walk, got frustrated as he was faster commando crawling.

My second little boy was around the 17mth mark, he could crawl and rathered that than trying to walk.

My little girl on the other hand was walking around 10mths. She was my third and had some keeping up to do and toys to pinch

None of them had hip problems.