moving around

we have yet to capture it on film yet, but greta is getting more and more mobile everyday. she continues to roll like crazy, but has also started pushing and pulling herself around on the floor. she will be sitting up and then will lean forward so that she is on her hands and knees. she then will either push herself with her feet/legs or pull herself in a sort of army crawl. she also sort of rocks back and forth while she is resting on all fours. she hasn't yet figured out to get both her arms and legs working at the same time. i think that would be considered crawling, and then we're in real trouble.