Very much an "OTHER"
Initially it was a queen with arms reach sidecar. Then all three in the queen. Then when dd got a bit bigger it was a queen (on the floor) and a twin mattress pushed together.
Eventually that turned into the current arrangement which is a queen on the floor pushed against an IKEA toddler bed (dd saw it and wouldn't let go!). The toddler bed is on a frame so it is perhaps three-four inches "higher" than the queen mattress which means dd loves rolling off and jumping back up...usually at 3am.
In June it will be a queen with a toddler bed plus the arms reach sidecar! Yoicks!