What do I do if father is now threatening parental kidnapping and is trying to get full custody?

It sounds as if you are in a dangerous situation, with a husband suffering from untreated PTSD. You have several choices. Protection orders from the courts are the best way to insure your safety and to protect your rights. But be forewarned: a protection order is only paper and will not stop a weapon. If you think you are in danger get police help immediately. First you may qualify for a domestic violence civil protection order if your husband has threatened you with bodily harm or you believe you are in immediate and present danger of him hurting you or the children. That would be the fastest way to protect you and the children. Ohio courts hold a hearing the same day the petition is filed and if good cause is shown, issue an order of protection the same day. You would have to go back to court for a contested hearing, but that would be true with any protection order you seek. Or you may qualify for a menacing by stalking protection order. You will need to state your husband is over eighteen and he is subjecting you to a pattern of conduct he knows may cause you to believe that he will cause physical harm to you or your children or may cause mental distress to you or your children. The first hearing for this order must be held by the day after filing. Or you may elect to file for divorce, and seek temporary custody of the children. There are other alternatives, but you should seek the counsel of an attorney with a domestic relations background. Given your situation, I would encourage you to proceed without delay. The above does not create a lawyer / client relationship, nor may it be taken as a legal opinion.