hey i suggest not listening to anyone except your bubs.... she doesn't know which order she is 'supposed' to reach her milestones in, so just let her reach them in whatever order she reaches them, she won't be 2 years old and unable to sit, IYKWIM...

i think my dd was around 7.5-8 months before she sat unassisted, she happened to crawl around the same time, can't remember which came first though, and really i guess it doesn't matter.... she did sit leaning forward supported by her hand for quite a while... i think she may have crawled first...

don't give it another thought, just let your baby lead the way and encourage her where you can... enjoy!!