Let him get older is the biggest. A three month old baby MAY sleep for 5 hours in a row. It is very rare for one this age to sleep longer than that and those moms are VERY lucky.
Babies usually start sleeping for 5 hours in a row around 4 months.
They start sleeping 8 hours in a row around 7 months.
They start sleeping from bedtime to morning around a year.
Of course, these are averages. Some babies sleep from bedtime to morning at just a few months old. Some don't do it until 3 or 4 years old.
While you are waiting for him to get older, set up a bedtime routine... dinner, bath, massage, storytime, etc. Pick whatever order you want and stick with it. Remember, you'll be doing this routine for the next few years so keep it under 45 minutes total.
at 8:42 PM on Jan. 22, 2009