How can I retain temporary custody and then possibly full custody of my nephew and niece?

[caomh]

My brother and my sister-in-law have been married for 6 years. Within those years my nephew and niece have watched their mother and father argue, and fight on an everyday basis. The arguments get so intense that their mother, my SIL beats, and hits my brother to the point of police being called time and time again. My brother now has a domestic violence charge because of his wifes lies. They both have been arrested for shoplifting together. My brother a few months ago went to jail for 3 months because of embezzling, and fraud charges. He gets out of jail and they move to Florida. (After having moved more than 20 times in the last year) they bounce from my parents, to his parents, to friends homes, to motels, over and over again. Now that they are in Florida, they got involved with the wrong crowd and my brother ended up getting badly hurt and now is scared of people coming after him and his family. It is just a mess. They are now homeless and living on money being sent down there to keep them off the streets. My family is not rich, we don't have the money to send each week to keep them in hotels. My nephew and niece are so withdrawn and hardly speak. When my brother was in the hospital she was left with a random stranger so that her mother could be with my brother in the hospital. The kids are scared all the time, crys and acts out a lot because they have a lack of supervision and trama from everything that has happened. My questions are this... I live on Virginia, since they have moved to Florida can I get temporary custody of her if the proper forms are filled out? Where can I find the proper forms? I know that most likely we will have to go though the court system but this is an emergency situation, with people still coming after them possibly. I need to get them here ASAP but I want to do it legally. If one of them gets sick for any reason, I won't be able to take them to the doctor. My brother and SIL are willing to give my husband and I temporary custody. I just don't know what forms to fill out. Florida's or Virginia's? Should I go for full custody after getting temporary custody? They love their children but they make the WORSE choices which have led them to where they are now. All the bouncing around home to home, fighting, domestic violence, shoplifting, arrests, jail time and such I want to give these children a stable loving home environment where they don't have to worry about sleeping on the streets, and on floors. I want custody of them badly but I don't want to hurt my SIL and brother. But I have to do what is best for the kids. I have my parents full support. Any advise that I can get will help me and my family greatly. Thank you so much.

[felabeorbt]

If the children are abused or in danger, call the police or CPS now.

For custody, call your lawyer. This is NOT something you can do without a lawyer.