Getting Custody or Guardianship of a Non-Biological Child in OH (Parents Play Virtually No Part in Her Life)

We have a 13 year old who we have basically taken over parenting duties for. Both biological parents are alive. Dad spent the last year unemployed (and to our knowledge is currently unemployed). He currently lives with his parents and multiple other family members. Mom is a habitual substance abuser, and we suspect she has fallen back into that pattern. The child lived with us last year for most of the summer and throughout the school year up until the end of March when Dad came and took her back. We did and still do provide 100% of parental support (food, shelter, clothes, etc.). We love her very much and want to make her part of our family. We are worried because at any given time either of her parents can just show up and take her away. We can't provide med. insurance, make legal decisions, etc. Shortly after he pulled her out of our house last year he moved for a few months and she ended up with her mom. She's back with us now and we want to be legally protected. Thanks