Sleep Baby Sleep

I think I need a refresher on how to help train my baby to sleep. She's up more than ever! She's 5 months old now. I switched her from our room to hers and from the bassinet to the crib. Thinking she's in her crib she might sleep better and longer. right??? She used to sleep until 3am then would get up at 5am but now she's getting up at 1 - 3 & 6am and sometimes will get up at 11pm. She's going down to sleep around 6pm.I'm trying to follow the Happy Healthy Sleep Book by Mark Weisbluth that worked like a charm with Chase but it's not working yet with Reece. So while I am still nursing at night, I try to put her down awake but I'm not so sure she still needs to eat at night. MY SIL stopped doing that with her child at 2-3 months after her doctors suggestion.Also, I'm trying the cry it out method but that's so hard. I'll only let her do it 20 minutes and then I give in. Give me the goods guys. I AM SO READY to get a full night's sleep in and I want that for Reece too.