Young kid from last town has been following the PCs and doing a rather good job at it. PCs weren't expecting to be followed so weren't worried and the boy/girl was careful. Notice the follower a couple days out of town, kid ran out of food and started getting careless. Followed the 'mighty adventurers' to see if he could join them. Father is a wealthy merchant. Bring him home, bring him with, send him off? What do you do with an unwelcomed guest.
Rain slowly builds, thunder and lightning continue to roll in. Road muddies, horse/wagon getting stuck in the mud. Thunder strikes coinciding with a deep hole a horse just walked in, horse panics, breaks its leg (maybe just sprain?). Horse is decompacitated and the rain just went from pouring to an all out monsoon. Shelter needs to be found, horse needs to be taken care of, covered in mud, add the posibility of items being lost to the confusion with the wind and dealing with spooked animals.