The first thing to do when trying to get full custody of your children is find out if there is a parenting plan in place.
A parenting plan is basically Washington’s version of custody in which timesharing and parental duties are mapped out. If you currently have a plan you can look to modify it or if you don’t, you should file a petition to get a parenting plan.
If you’re still married, you will also need to file for divorce or legal separation. The court will look at a variety of things to determine who the best parent for custodial rights is. These things include being in a stable situation and flexible employment. Also, issues like drug or alcohol use, criminal history, and domestic violence history can radically affect custody rights.