We officially have an unsupported sitter. I think she would have been able to do this a little while ago. I noticed her doing it in her high chair a week or so ago but just haven't set her on the floor in a sitting position for a little while. Sunday I set her down to do some practicing and what do you know? She is an old pro at this sitting thing. She will be 6 months old on Thursday.
She is getting really close to crawling also. She can pull her knees up under her and rock back and forth. Yesterday she inched her way over to a toy on the floor by doing her "push up"s and falling.