Get and read this book: Healthy Sleep Habits, Happy Child by Marc Weissbluth (Paperback - April 12, 1999). It worked wonders with our first child. Then, when he was 2, I was pregnant with our second child. Then, the only way he would fall asleep was when I was with him in his room (falling asleep as well, but oh, well, I'm Mom!). There was a whole lot of turmoil in our lives at that time, the second baby, my husband's work hours, my work, moving into a new house, etc. etc. So, I just hung in there with him and let him fall asleep with me next to him. This lasted for a few months, and then he got past it. But, when things are chaotic, stressful, too busy and overwhelming, my now 9 year old asks me to lie down with him and cuddle. That reaching out is very telling, and it's one of the few ways this boy of mine will. So, I recommend you read the book, it is insightful, and then hug and cuddle your grandchild, and stay with her as long as this is a security issue and not a control issue. If her biological mother is coming and going and no set schedule etc, her psychological security is probably taxed. In case no one has said anything to you, You and your husband are pretty fantastic and doing the right thing. Good luck.