The one question that has bother me all of my years. "Why do the children have to suffer?" Adults can cope, but not children. Dreams shattered, trust broken, love turning to hate.
Children are very resilient, especially when younger. As they get older than 6 or 7, the damage is harder to overcome, but it can be done with lots of patience and love (both in quantities one might not think possible!). I worked as a school counselor for 36 years and have dealt with children ages 11 to 18 and have dealt with many who were in horrid situations. With the help of our social workers, police, lawyers and various agencies, many were helped - many could not be helped, unfortunately, for a variety of reasons, legal and familial. Through it all, I provided the love, encouragement and support as best I could. Not all were happy endings, but those that were made it worthwhile.
If you like the theme of building a family of "tossed away" or homeless children, I recommend another series on this site: "The Castaway Hotel" by Bill W.