Belly time princess

Bianca's getting really good at belly time. If we're standing behind her and to the side she seems to elongate her neck and twist her head like turtle, looking for us. I keep hoping that she'll lose her balance and induce a rollover, but she's too strong. Her sitting up has also gotten much better. She reaches for her favorite toys - only so she can put them in her mouth - and she starts to do a sit up when she's laying on her back trying to raise herself to a sitting position.