We bought an Ikea Kura bed and are going to attempt room sharing! Then we'll be able to turn Olive's room into an office, which would be awesome because we need the space.
We're just waiting for the mattress to be delivered. They are 2 1/2 and 4 1/2, and they can share for at least a couple of years.
Are your LO's sharing a room? How is it?