night terrors

Has anyone had to deal with their little ones having night terrors. My son will be 17 months on the 13 and last couple nights it has been bad. Finally get him to sleep and less than an hour he's screaming and crying but not awake. We just hold him and try to comfort him until it's over. Sometimes it's an hour or less before he has another. But tonight not even 5 minutes before he starts again. Wondering if any one has any advice or suggestions. Greatly appreciated. It's hard watching your baby go through this and can't help him. I cried with him tonight.