We converted a crib into a very low toddler bunk bed. We used a convertible crib and an extra rail from another convertible crib we have.

We cut the legs down by about 6 inches so the horizontal rail was even with the top of the bottom mattress.
We cut the legs down by about 6 inches so the horizontal rail was even with the top of the bottom mattress.
This is the completed conversion. The little girls are in the first picture, my tow seven year olds are in the second picture and the last photo is showing the lowness of the top bed. It is actually lower that the bed we have in the master bedroom.