have you checked the Social Security death index ? I found 7 Milligans whose last residence was Clark Co., WA.
I found 11 Milligans living in Vancouver through the white pages online.
I am going to the local genealogy library on friday. will see if I can find an obit for Martin. if I can, do you want a copy or should I just make a list of survivors ?
you can email me direct at firstname.lastname@example.org