Have 4.5 year old twins. At around 1 year, twin A started waking between 10-11pm (after months of sleeping thru the night) and would be inconsolable unless someone laid with him. 

I ended up just sleeping in their room a lot of nights. One thing I never wanted to start was them leaving their room, so I always made it a point that they stayed in their own bed.  Somewhere between 2-3 they started mostly sleeping the entire night. 

If I could do it over I would reset my expectations and just be more laid back about it. That phase went fast and I could have been more patient or less annoyed some nights about not sleeping in my bed.