Sitting Up Instead of Going to Sleep!

I was so excited when Ariella finally started sitting up from laying down and then pulling up. She's even starting a little bit of cruising now. BUT! She won't fall asleep in her crib anymore! I used to put her in her crib awake. I'd sing to her for a bit or play her seahorse music toy, maybe rubbing her back a bit. She'd usually settle down within 5 minutes and go to sleep.

She won't do that anymore, though! I lay her down and before I even get myself fully standing straight up again, she's sitting up! Last night I was up with her for 30 minutes, singing, rocking, continually laying her back down, trying to keep her laying down by holding her down with one hand and then rubbing her back with the other. No luck.

So, I figured I should try to leave her there by herself to setting down. Nope! The child was screaming for 20 minutes! So, I went and got her, put her in her swing, and she was out like a light within like 30 second! I know it's just a phase because of learning all of these new skills, but it's really getting difficult for me without getting a decent night's sleep. Also, when she wakes in the middle of the night, she can't go back to sleep anymore either because she sits up. Aaahhhh!!! Tired mommy here.