There are different levels of restraining orders and obtaining one through the divorce process is usually weaker than obtaining one through just getting a restraining order. My ex's initial restraining order said he wasn't to disturb my peace or harass me. After he assaulted me in a parking lot (neutral location to swap the children mandated by the court), the prosecutor's office has bumped it up to a "no-hostile contact" order, which just means he's not allowed to assault me, again. Sarcastic LOL.
As far as the children, Washington state requires extensive documentation to keep one parent from the child, EVEN if the parent has a past history of violence towards the other parent. It would need to be proved that parent was a definite threat to the children, not just to the other parent.