I know that a married couple needs to have a baby and when it grows up you can send them off to become a traveler, but how does the streetpass traveler thing all work?
2 Answers
After your baby grows up, you get the choice of selecting if he will live on you island or if he will become a traveler. When you chose traveler, the baby becomes a traveler and will put a outfit on. After the game credits are finished, he will be waiting for the next Streetpass on the port. When hes send away, you'll see a little animation of the traveler jumping in the boat and sailing away. From time to time, you will receive Spotpass notifications where your traveler writes a letter to his original parents which plays like a video. He can also get homesick and visit his parent after which he goes to continue his journey.
When you receive a traveler via Spotpass, he will be at the campsite, where you can interact with him. The next day he will leave the port to go to an other island.
When your baby has grown, you can choose whether you want it to travel or to stay. When you choose to travel, it will go to the port and wait there until it finds a 3ds to go. The traveller an travel when one 3ds is closed and the other opened (you both need to play the game and you need to have spotpass turned on). It can take some time and it will not always work. When you have a traveller on your camping, you an give it stuff and it can sell you specialities.
