We live in Washington State. My boyfriend's ex-wife got sick recently and is afraid she may pass away, so she is hiring a lawyer to draw up paperwork so that her parents will have custody of their 6 year old son if she does die. My boyfriend wants his son to live with him if that happens, however he is worried that if his ex draws up paperwork, her parents will get custody and he won't have his son live with him. Is that possible?