Angry stepchild - can't tolerate violence

[AzMom]

I have 2 children, 15 and 13. My fiancee also has 2 children, 13 and 10. He did not have a very close relationship to them for a few years, due to extreme problems with their Mom. He has been working to improve their relationship and has started counseling with the 13 yr old son. We spend some time all together but he spends much of their visits doing things with his kids, to help strengthen that relationship. We recently went on a weekend away with his kids and my 15 yr old son. His 13 yr old threw a temper tantrum and locked himself in a room. He used threats of violence against his dad and tried to choke my son. We finally got him calmed down, but this behavior cannot go on. We have heard that he does this type of thing quite often when he is with him mom, but this was our first experience with it. We are going to be moving in together soon. His kids will live with their mom as primary residence, but I am very concerned about how to handle this behavior going forward. I am dealing with my own kids teenage issues, which pale in comparison, but nonetheless, we need some help and would appreciate any advice. Thank you!

[Mike Bradley]

Dear Mom,
Blending families with teenagers who have issues with their parents is the Super Bowl of parenting---the challenges are huge. I hate to add another counseling session to your world, but your future blended family needs to meet as a group with a therapist to work on these issues BEFORE the bags get unpacked. Otherwise they may end up thrown through your windows.
Invest in some therapy time now while these kids can still retreat to their old familiar worlds for comfort and cooling off before you force them to co-exist in a house. Remember, they didn't volunteer to have a new family, they got drafted. So expect them to be angry and upset about these changes.
Good luck.