Sleep Suggestions

I am hoping for some ideas for my LO. She is 20 months old and was sleeping from 8 30pm until about 7 am. The last week and a half, she has gone to bed at the same time but wakes up anywhere between 11pm and 2 am and stays awake until 5am or later. My husband and I are exhausted! We've tried lavendar oil, lavendar bubble bath, sitting by her bed, patting her back, rubbing her forehead and more. Every night we follow our routine of calm activities before bed and she has her bottle. Any suggestions?? I would really appreciate them!