Sleep Training

My almost-six-month-old has regressed when it comes to getting enough sleep recently. I haven't been diligent about giving her naps in her crib (too often she ends up napping in her carseat near the family hubbub), and she's now old enough that it's time she had regularly scheduled naps. How did nearly six months pass already? Also, I've slipped back into getting up in the night every two hours instead of letting her put herself back to sleep. She used to sleep for 4-6 hours for at least one stretch at the beginning of the night, but she's stopped doing that. It can't be due to hunger, for she eats a lot, including milk (of course), rice cereal, puffs, and pureed fruit. We are both very tired. It's starting to interfere with my daily activities. So we are doing a little "sleep training," which consists mostly of me NOT getting up every two hours when she cries out. Here's hoping she's a fast learner!

Update (12/7/2014): And it turns out she is! We got a six hour stretch of sleep last night. :) I'm going to help her love resting her head on her crib mattress by getting her a chenille crib sheet for Christmas. (As the fifth girl, she doesn't need any toys under the tree!)