One thing I can say, Sera might know Forrest rather well, due to them both being orphans, although he is quite a lot older than her, so I imagine Forrest taught her a few survival skills and so on. How 'bout it, [@Aquaknight]?

For Tivo, I can see her meeting him on one of her scavenger hunts once in a while. [@Ebonsquire]

Maybe Rahna for the herbs and medicine, or better Rahna's mother and by association Rahna. [@Rekaigan]

Since I made Sera quite the loner, I don't have anything else right now. If somebody comes up with something, shoot it at me.