How Did She Do This?

Ana-Patrick was in her pack and play watching a DVD while I was in the kitchen cooking dinner. I would poke my head around the corner to check on her and the 2nd or 3rd time I did, this is what I saw!! I couldn't believe first of all that she was just standing up watching her movie (lol) and second of all that she was able to pull up without anything to use to pull on. It still remains a mystery...