Toddler won't sleep in his room alone
If your toddler has never slept in their room alone, they may just not be ready. Our big kids slept in our room for years, but just recently moved to their own rooms voluntarily. They now stay in the room most nights, or will sometimes come to our room around 4 or 5 in the morning. Some people will toddler-proof the entire room and install a lock on the door and lock the child in the room at night, forcing them to stay in the room until Mom or Dad lets them out in the morning. Our family never felt comfortable with that, but I would imagine it would work faster than waiting for your child to make the decision on their own.
Depending on the age of your toddler, you may want to talk to them about why they won't sleep in their room. Mason told us he was afraid of the dark, so simply adding a small Pillow Pet stuffed animal that lights up we were able to make him comfortable enough that he stays in his room.
How did you get your child to sleep in their own room?
We had Avery sleeping in her own room at about 2 months old. She was sleeping through the night at that point and her room is only about 5 feet away from ours. We also found that she'd sleep longer in the morning and go to be earlier without us distracting her :)
Heck, I even sleep with a nightlight and I am 36.