Last week, Aria had been sleeping great--going to sleep around 10pm and sleeping for 5-6 hours. This week, she won't go to sleep until closer to midnight and is waking every 3-4 hours until about 11am. I'm not as concerned about her sleeping again for 6 hours, though that would be nice. It's the going to bed at midnight part that doesn't work for us.
Is this just part of her 6-week growth spurt? How can we shift her sleep schedule so she'll go to sleep earlier and wake up earlier?