My daughter is 9 years old and lives with her mother, and mothers new husband, she is very unhappy there, depressed, and keeps asking if she can come and live with me her dad. She is left at home with our oldest daughter is eleven years old, some times for a couple of hours some times for a whole day. They have to cook for themselves, and mother keeps discussing her own issues and what she thinks about myself and my wife to them. My daughter wants me to go to court and see if she can come and live with me. As she is only nine years old I would like to know what here chances are, we are all living in germany. What would happen if I did file for custody for my youngest daughter.

I would be very grateful for any information that can be given on this subject

Consult a local attorney. A 9 year old is kind of on the young side to have her preferences listended to, but maybe German law is different.

If the children are 11 and 9 and being left without adult supervision, then the local children's services agency might have something to say about that.

Are the children in Germany also and do you have reguler visitation at this time ?