We bought my son a convertible crib which works as a crib, daybed with side-rail, daybed, or a full-sized bed. We recently went through the transformation to move his room from baby to toddler!
For the original room post see:
Below is his new updated room with a big kid bed!
Mason was very excited and helped along the way.
Sister helped too!
The bed set was purchased here, and comes in crib, twin, full or queen: