My baby is 4  months old, how do I get my baby to sleep throught the night?  I'm sooo sleepy...Help

I've got good news and bad news for you. :-)

The good news is that she's getting there. The bad news is that the medical definition of "sleeping through the night" means sleeping one 4-5 hour stretch. So waking up 2-4 times a night is still very developmentally and biologically appropriate for an infant.

Babies have small tummies and need to wake up to fill them. (And stuffing them in the hopes of getting more sleep doesn't work. They've done studies on that one. If you're lucky, you'll get a baby who sleeps the same. If you're not, you'll get a baby who gets uncomfortable gas from being too full and wakes up more often rather than less.)

The bigger and older she gets, the longer she'll be able to go. My daughter started sleeping longer once she hit about 10 pounds -- that's when she started going for one 4 hour stretch, usually midnight to 4 am. By six months she was starting to go longer. (Although then you run into night waking due to teething, growth spurts, and developmental milestones!)

My son started out at 10 lbs. 4 oz. and has slept a good 4-5 stretch once a night since birth, from roughly 7 to 11 pm. He's over 20 pounds now and is starting to sleep for 6 hours or so.

Hang in there, mama. Don't try to force your baby into different sleeping habits. That's alternately frustrating for you or spirit-breaking for them (i.e. "cry it out" -- horrid practice). Instead, try to work *with* her. Nap when she naps during the day, as much as possible. Enlist your partner to help with the nighttime parenting. I do the nursing and diaper changes for our youngest at night, my husband takes care of our older child when she asks for water, needs calming down because of teething, etc. When we had just one, I did the nursing and he did the diaper changes so neither of us was getting too sleep deprived