Extended family, maybe there is a cousin or child of a close friend. You have to make an effort to maintain a relationship, but you should find people you can trust, stay in touch, broach the uncomfortable conversations, and make legal preperations..
Even children and relatives can't all be trusted. My wife's parents always wanted her to manage their healthcare and financial concerns as the aged, but they did little pre-planning and when it came down to it, there was too much opportunity for her older siblings to step in and strip their assets.
They are not in a terrible situation, but had they been willing to accept a small amount of help earlier, and address legal issues we brought up, they would be in a much better place.