I have having a terrible time getting my 5.5 week old DD to sleep in her crib (on her back). She absolutely HATES being on flat on her back. She will sleep in the swing and her bassinette (both are at an angle so she's not flat on her back). She'll sleep on anyone's chest or in their arms but the minute you try to lay her flat on her back, she wakes up - no matter what state of sleep she is in. I am very consistent during the day about her naps but because she wakes up as soon as I try to put her down in her crib, she isn't sleeping for long periods of time. She loves to sleep on her stomach and she will sleep in her crib on her stomach without a problem. But I am worried about SIDS. Do I keep trying or wait until she's older? Any advice? Suggestions?