Yes Yes Yes, neuter asap! You may still have some problems ahead of you as there is same sex aggression with Jack Russell's. Be aware of this and do some research on it. Exercise, Exercise, Exercise. Classes would do good also. You need to get them outside and get them to experience all kinds of things, When they start to howl and bark at something coming their way, immediately and abruptly turn in the opposite direction till they settle down. When they do reverse your direction again, if they start up again, reverse direction again. Just be careful and I wouldn't leave the two males loose alone when you are not there to monitor them. Especially once the hormones kick in. They may fight for dominance.
