The ten year old girl has natural golden blonde hair. The 23 year old woman (see sunglasses photo) has very dark, nearly black roots dyed light ash blonde. Definitely not the same person.

That and the fact the dead woman grew up in California and was well known in her community at the same times this younger girl was living in DC and Martha's Vineyard.

I had dirty blonde hair as a child to have it turn much darker. Forced veganism.

That's not how that works. I had the world's fairest blonde hair as a kid. As an adult my hair is brown with barely a hint of blonde in it.