Can you sue ex husband for mental distress and causing PTSD in both you and your son?

Yes, it is possible to sue an ex-husband for mental distress and causing PTSD, but the success of such a lawsuit depends on various factors, including the evidence of harm, the nature of the actions that caused the distress, and the applicable laws in your jurisdiction. You would need to demonstrate that his actions were intentional or negligent and directly resulted in emotional harm to both you and your son. Consulting with a lawyer who specializes in family law or personal injury would be essential to assess the viability of your case.