A situation

Hi all. Im not really sure where to post this, but since it is happening in Indiana, I thought here might be the best place to start. I'm also not really sure what the exact question is. so I guess right now, just opinions is what I am after. My almost son in law has a 2.5 year old son. His exwife has a 5-6 year old son from a previous relationship. and she is married to a man who has 2 boys , both from different mothers.( alot to absorb already huh?) this past weekend he took is son D home to his mother who met them at the door with some disturbing news, as well as some very limited info. or none really. Dad was handed a note with the name and number of a cps case worker, and that of a pros. atty. and told that there had been an incidense of one of the new husbands boys sexually molesting her older son. but she would not go into detail. told him only that it had nothign to do with his son and if he wanted info to call the numbers she gave him. He was struck speechless and coudnt think at all.. and left with his head reeling. they called me. It was hard to give any advise due to the fact that there was such limited info. He was assured the accused was not going to be in the home for some period of time. I did tell him that regardless of her saying she wasnt going into detail.If it had been me. I would have said either tell me what is going on or I am taking D back home with me!! that didnt happen and we all had quite a sleepless night thinking and wondering what was going on. but still telling ourselves D was fine because CPS would not have allowed any of the kids to stay there if they werent considered to be safe. It was after the initial shock and while we were all hashing over WTH was going on that my daughter stated that there were a few things that bothered her now, knowing something is going on , regarding a bath that she had given D a week ago.. and while trying to dry him off he jumped when she reached his nether parts saying ouch and when she asked h im what was ouch he said she touched his ... stuff. I dont recall what his name for it is.. she said she noticed it was a bit purplish.. and maybe a bit odd looking than normal. but that she has a daughter and really doesnt know what they are 'suppose " to looke like at any given time.. of course she would know if it was really unusual.. but she just brushed it off at the moment. They also always have alot of behavioral issues with him when it is time to go home to Mommy's.He has fits and gives fight as soon as they say its time to go home. They sometimes ease during the ride but start again as soon as they turn onto the road. Yesterday dad was able to speak to the case worker who had been expecting his call and was told that the 14 year old step son was caught " doing something" to the 5 or 6 year old ( her son) he was caught by his father. We were suprised that Mom was the one that contacted CPS . maybe she didnt know who else to call. thinking about it.. Im not sure I would really know who other than them to get advise from. They sent someone out.. and the 14 year old admitted to the act. ( we still dont know exactly what) and that it wasnt the first time. This is how the prosecutor became involved. His age and the admission. The case worker only stated that it is really in the prosecutors hands now and that cps is not involved with any investigation. at least at this point. The perpetrator ( at this point) is not allowed into the home for 30 days , that could wind up being longer, and the victim is having foresic testing done. they cant make any determination of what happened until all this is complete. He is also being put into therapy. So.. with the admission, we have wonder if something has ever happened to D, as well as where did this boy get this tendancy from. It is usually learned. Has he been molested and by whom.. and who is to say that it hasnt happened with his own half brother who might also follow the trait?? ohhhhh soo many questions. and they ask me to come here.. because they know what a help you have all been to me during my ordeal and the adoption of my grandson/ son! They would like to take full custody of D. But right now. Mom is his custodial parent. CPS told him that if something happened and he was removed obvioulsly dad would get him. but right now that isnt the case. He talked of getting a lawyer to try to get custody without CPS ( just like one would during a divorce) but he knows she will fight tooth and nail against that. We think that the fact that the atmosphere in that home isnt good now.. and who is to say it ever will be. It definatley leave you with an uneasy feeling. Like we just have to wait till he is harmed to do something? so I guess.. the question is.. what would you do?? Or how would you manage to do it?? I hope this makes sence.. my head tells me he needs to contact his lawyer.. and ask to have custody awarded to him because of these issues. I think he is just lookiing for reasurance that he isnt 'jumping the gun" I told him his responsibility is to D. If he feels he may be in harms way he should do whatever he can to protect him. if he it turns out there was error.. he will know he did what he had to to protect D. If he does nothing.. how will he live with himself if something does happen!? so. this really isnt a foster issue. nor an adoption issue.. but a wellfare of the child issue. Does he have grounds .. does he stand a chance of gaining custody?? I still feel as if I dont know what Im asking other than the part " what would you do?" any takers here??