A number of people I know from South Florida participate in LifeCycle. Some have HIV or even AIDS themselves, and may be riding in memory of someone they lost to AIDS, typically a partner or family member, even just a friend or acquaintance.
It's a custom to carry some kind of memento of the late person on the bike, a photo or piece of jewelry or something. Apparently this father was carrying a photo of his son.
We have the same custom in our shorter SMART Ride to Key West, only 165 miles (I doubt I have the stamina for LifeCycle, nor would I leave my husband for over a week with his health concerns). I carry a ring worn by my late first partner when I ride it, and at least half the other riders carry similar objects.
And some of our riders are parents, mothers & fathers, of a son they lost to AIDS. And if they don't ride they do crew, which is nearly 1/3 of our participants.
This father's story is touching. Tragically it is not unique. All the more reason to not forget about HIV/AIDS issues during this current euphoria over gay marriage. We may be defeating our anti-gay social & political opponents, but that health scourge remains with us.