Cribbs version

There were four in the bed...
and the big one said, "Roll over, Roll over!" So they all rolled over and one fell out.

There were three in the bed...

and the big one said, "Roll over, Roll over!" So they all rolled over and one fell out.

There were two in the bed...

and the big one said, "Roll over, Roll over!" So they all rolled over and one fell out.

There was one in the bed...

and she rolled over and she fell out!