DD and DS share a room and it is only a recent thing. I moved his bed in there before he was ready to transition to it, just so that DD could get used to it. Like Mel no toys are in their room.
The first nigh she had a fit about actually having to share and did not want him in there despite his bed linen being on the bed lol. He came in with me about 4am that morning and at 6am we were woken by an angry 5yo wanting to know where her brother was and that I was to leave him there all night the following night!

She got better at leaving him alone while he slept, and he got better at sleeping through her noise. I did have to shut the door for a bit though.