My five-month-old baby hardly sleeps during the night? What should I do?

It might be that your child mixes up day and night. Do allow some light in the room in the daytime so that the baby can differentiate between night and day. At 4 mths old, it will be good to have a routine where she knows when is time to drink and sleep. They might have growth spurt in certain months and it is normal. See http://www.babycentre.co.uk/a25012757/baby-growth-spurts and hope this info helps you. :)