Psycho kidnapping

Okay… My brother’s ~x~ gave up her rights to her oldest son when she gave birth at the hospital and csb gave him right to my brother. Then my brother found this other girl which I love very much and got her pregnant 6 months later he went back to his son’s mom and got her pregnant. Then went back to his girlfriend the one I like and they got an apartment together. Then they decided to let his ~x~ move in because she had no where else to go. Well turns out she bi-polar and one day my brother made her mad and she locked herself in their room with my baby niece in there and tried to stab herself with a screw-driver so my brother broke down the door and tried to take the screw-driver away from her and while he was doing that his girlfriend called the cops and they amitted her to the hospital for a month then she gave birth to her son. 6 months later she got her own apartment and 2 wks later the neighbor who I went to school with call the fire-department because she smelled something that didn’t seen rgiht to her, and sure enough they found crack under the baby mattress and they took him out right away and arrested her, she got away to get the charges dropped. Now she lives in florida with my nephew and won’t let anyone see him and we can’t do anything about it unless she moves back here which I doubt it. But I really miss him and I want to hurt her so much. She is gonnah come up here from florida in a couple of weeks and my brother is gonnah let her take his oldest son to florida for a month but I know that she will take full custody of him and we won’t see him ever again. I wan’t to have proof that she can take full custody of him there and there is nothing we can do about it. We could get her for kidnapping but it could take years to find him. And he don’t want to go because he knows he won’t ever see his family that he knows. What should I do to prove it to him, that she can???