First a little background:

BM has two kids and another on the way. None of them have the same fathers. Her oldest is ten (his father is actively in the picture), middle - five (which is DH's son) and she is about five months pregnant with her third and currently living with that baby’s father.

DH and I have no children yet and DH has no other children.

About a week and a half ago I was driving in the car with SS and he told me a story about how his brother grabbed a knife from the kitchen and threatened to kill himself. Now he is five and has been known to stretch the truth, but I did my best to talk to him about the situation and then told DH about it as well. Then the next day I was talking to BM and she did confirm the her oldest did do that and explained how she thought it was caused by the medication he was on for ADD, which I guess has been known to cause depression, etc. They have since taken him off that medication and are trying something new. Sounded to me like they are taking the correct steps to address the problem, so I didn’t dwell on it too much.

SS came back this week and was talking to DH and I about the situation and apparently he witnessed the entire show go down and it seems to be bothering him a lot because he has brought it up every day. He has asked us questions about why his brother would do that. He was also apparently told that if his brother doesn’t get better he will get locked away in a hospital forever and he will never see him again. Which understanably has SS upset because he absolutly adores his big brother.

Now unfortunately BM avoids serious conversations at all costs. She would rather lie to her children then have to have a tough conversation with them, which leaves DH trying to pick up the pieces, without all of the information. I usually let DH and BM talk to SS about topics that are tough or personal because I believe that it’s in SS’s best interest to hear it come from his mom and dad. But when DH brought it up to BM, she said there is nothing to worry about and that she didn't have time to deal with it.

My questions are:
What is the best way to handle this / explain and talk to a five year old about what he saw and how he’s feeling? I realize the SS could be making a bigger deal out of it than necessary to get our attention, I just don’t want to ignore something like this, or draw too much attention to it, so I’m a little lost.

Also, someone brought to my attention today that SS could also be at risk if his brother is having harmful thoughts, and that he could also try to harm SS as well. I'm not sure I believe that, but I really don't know enough about the topic or about his older brother to be sure. So I just need some advice. Being that SS is the only child in our household, we tend to focus most of our time and energy on him and it’s hard to tell when we are being overly protective and when we’re not being protective enough. If anyone has experienced this before or knows how we should handle this, please feel free to share your opinions. Even if you think we are worrying too much about it. Neither DH or I have ever had to experience anything like this so we need help! Thanks