My first two girls were big time movers in the crib. They often woke themselves up when they would turn in circles as the slept and get stuck when turned sideways. As a result, I had to move both of them into big beds (full size) at 18 months. I never thought twice about it. I did get a railing for each side of the bed just in case (relatively inexpensive). My first had the railings off by two. My second is a little over 3 y/o and we still have a railing up on one side. As far as getting out of bed, neither of my girls really did in the beginning, they just called for mom or dad. And when they did, there was a hallway night light just in case, but never a problem. And our bedroom is downstairs and theirs is upstairs. Why even do a mattress on the floor? Good luck!
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My first two girls were big time movers in the crib. They would often wake themselves up when they would turn in circles as they slept and get stuck when turned sideways. As a result, I had to move both of them into big beds (full size) at 18 months. I never thought twice about it. I did get a railing for each side of the bed just in case (relatively inexpensive). My first had the railings off by two. My second is a little over 3 y/o and we still have a railing up on one side. As far as getting out of bed, neither of my girls really did in the beginning, they just called for mom or dad. And when they did, there was a hallway night light just in case, but never a problem. And our bedroom is downstairs and theirs is upstairs. Why even do a mattress on the floor? Good luck!