I have certainly done my share of drugs. Many many years ago I had several experiences with pcp! Not a good thing. But I dont think I need to go into details since you have a good idea already. You ask what came over your sister to make her do this drug. I do not think she picked that particular drug, I think it was available when she wanted to use. It could have been anything, I think. I always felt any child deserves a good, stable, loving responsible parent. So even though I was into drugs, I did not involve any children. Mess up your own life not a child! I hope she will stop before her child is really hurt. If not, I hate to say this but I would try to get her child taken from her care! I am sorry you are going through this. Everyday I try to make up for all I put my family through with my addiction. Good luck to you