my brother killed himself with his girlfriends gun, she left it out. Her ex killed himself too. she didnt call the cops

Question

is there anything we can do to make sure there is not a third person this will happen to

Joanne Reisman · Answer

This isn't a legal question.  However using common sense would go a long way to prevent such tragedies.  You and the surviving members of your family should either get rid of any guns you have in your homes or be a responsible gun owner and get a secure gun safe and store you guns there.   If someone you know is suffering from depression educate yourself as to what you can do to spot extreme depressive episodes and as to what you can do to guide the person to get some type of help.   Take care of yourself.  Tendencies toward substance addiction and mental health issues can be tied to hereditary factors. 
 
As for peoples choices for partners, we don't have much control over this.  We also can't force people to get substance abuse treatment or therapy.   But there are ways to stage what is called an intervention.   So if another friend or family member is showing obvious signs of distress, you could research how to organize an intervention which leads to the person agreeing to enter an in patient treatment program.   Some people can enter recovery and go on to have stable lives.  Some people relapse and take their lives.  All you can do is your best to help.  But you also need to lead by example which means dealing with any similar issues you have as well.

Q: my brother killed himself with his girlfriends gun, she left it out. Her ex killed himself too. she didnt call the cops