Reoccurring Overnight Sitter Needed For 20 Month Old

I am looking for an overnight sitter for my daughter, my schedule does vary week by week, however I get my schedule for a month at a time, and about a month in advance. I work overnight in the hospital as a RN. Hours would be from 6 p.m. - 8 a.m. on my scheduled nights. My daughter does sleep through the night once she is asleep and will likely not wake up before I get home. On the occasion she does wake up, she generally goes right back down with a cup of milk or water and a pat on the back. I believe this should be an easy job. I will provide dinner every night.