The two of you drink from the creek. Willis is a bit worried, but after you show him it's okay, he drinks too. You can't really taste it much, you're drinking too quickly, but it does quench your thirst.
You end up heading over to Willis's family house for the evening meal, and promise to meet up several times during the rest of the week. His family does seem fairly neat, but they always seem tired when you come over, so you know they're happy to have you play with him. They're weavers, and you know that for them the busy season is winter, where they spend pretty much all day doing boring work making clothes for most of the rest of the village. It's also why Willis goes and lives with his city family.. too much energy to sit around all winter without messing everything up.
Over the course of the following weeks, the two of you enjoy your summer together, going out most days to play in one way or another, exploring the woods, running through the village, chasing stray dogs until they get tired, doing some fishing and some rafting, and generally enjoying the summer.
..but as the end of summer nears, you have some more serious discussions. It seems Willis's family wants him to take up a trade and start earning his own way through life, so this might be the last free summer you have together. He's kind of ambivalent about what he wants to do going forward, and as your friend, wants your advice.
What do you tell him?
You should use your energy and your brains and be a copper. You can track down crooks, hunt bandits, and you'd get to learn to fight!
You should be a sailor! You get to be at sea all the time, and although they make you work hard, you'll do well there. You could rise to be a captain and make your fortune at sea. You're tough enough for the life.
You should be an explorer and adventurer. You can use your quick thinking and speed to be a tomb raider or a looter, and recover all kinds of treasure. Like Uncle, but you can get more recent and modern stuff.
You should be an explorer and adventurer. You can use your skill at arms and strength to be an escort, where you protect people like Uncle, and fight monsters to keep them safe.
You both know that you'd like to learn battle magic, but neither of you can afford the money to get training in it.