D.N.
I had triplets and they all shared a crib for the first 4 months. Then my son got his own crib and my girls slept together until they were just past 2 yrs old. We never had a problem, except when they would get sneaky and climb out. They say you should not have more than one in a crib but we had no issues with it. Also, I did not use a bumper beyond the first few months. Since they slept together from the beginning, they usually went to sleep fine with occasional playing around instead. We didn't co-sleep because it was just too much in one bed. We tried it the first few days. They had latch problems so they got breastmilk in a bottle.