Never let anyone play rough with your baby. Babies' bones and organs are soft and easily damaged. Never shake your baby. Even though your baby is still tiny and perhaps sleeps in a portable bassinet, you may be considering buying a crib. Most new cribs sold today are fairly safe, but it pays to double check against the following standards.
Babies can squeeze their heads through more widely spaced slats and strangle.
Make certain that the mattress is firm and fits snugly. Babies can get trapped in the holes created by poorly fitted mattresses. Keep the crib rails up as a safety precaution. When fully raised, each crib side should be a minimum of 26 inches above the mattress. When lowered, the sides should be high enough so that your baby cannot fall or roll out of the crib.