I read an article on the BBC written by a cultural anthropologist who helps identify bodies found in the Sonora desert, which are almost all migrants from Central America trying to get into the US:
http://www.bbc.co.uk/news/magazine-21029783
Something she wrote about some of her experiences really resonated with Bob's case for me.
While his daughters may not show any apparent signs of grieving for him or even wanting to know what happened to him, I can't help but wonder what his grandchildren are making of it. Did they know Grandfather Bob? If not, do they ever wonder why their father doesn't apparently have a father, as the fathers of their friends probably do?
When they get old enough to ask pointed questions and get on the internet to find the answers, will they be trapped in grief that cannot be truly resolved?
Someone knows the answers.