You would need to file a third party custody action which can be complicated. If you can get Mom an Dad to sign off on the petition, then it is not that difficult. Absent that agreement, however, it is unlikely that you could do this by yourself because it involves a full trial with lots of procedural steps that can be avoided. At the very least, you need to spend some money to have a consultation with a local family law attorney.
Hope this helps
The information is for general information purposes only. Nothing stated above should be taken as legal advice for any individual case or situation.
Guardianship would not necessarily trump the natural parents' custody rights; for that you would need to initiate a third-party custody proceeding, and both parents would have the right to participate in the proceeding. If you won, the end result would be a parenting plan/residential schedule that spells out when the child is to reside with you, and what visitation the parents would have.
If cost is a concern, you could contact the Northwest Women's Law Center in Seattle; I believe they have a list of attorneys willing to take custody cases like this on a pro bono or sliding scale basis.
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