How do my other characters go online?

[Jimboi17]

My nephews went ahead and created a character of their own. They just got out of their tents and now I was wondering how do they play online? My friends list is not appearing on theirs. Which FC do they share?

 

[Superpenguin]

They share the same 3DS's friend lsit, but they get their own Best Friends List. Remember they have to get their picture taken before traveling.

 

[JKDOS]

If friends aint showing up then non of them are online...