We have done it! If I remember right, we had fastpasses for it, so Steve took Colton and I sat with Connor and then I took Colton while Steve sat with Connor. If you don't have a FP, there are CM's there at the end of the line doing height checks. I am sure they will tell you how to handle it, but what I think happens is they give you a pass to go to through the FP line once the first rider comes back. Have fun!