my daughter is 6 months 19 days old. since starting she has very disturbed sleep but around 3-4 months at night she started sleeping for 4 -5 hours on a stretch but after 5 months she sleeps but for v less duration like 15 mins even if it is 1 or 2 hr on a stretch it's very disturbed one . she cries though she is sleepy n unable to sleep then I hav to take on arms n then sometimes she sleeps . what could b the reason why she is not having peaceful sleep ? due to this m unable to sleep whole day whole night