Yeah, Travis didn't seem to have a buddy (and Reed kinda lost his when the writers committed to the Tucker/T'Pol relationship). Briefly, during the episode where Reed, Hoshi and Travis are possessed by aliens with a particular horrific virus (I am blanking on the name of the ep), Reed and Travis are shown playing chess together. That could have been more for both characters, but that was more or less it.
I could have seen Travis with some below decks characters as well, even briefly - "Hiya, Sue, you going to Movie Night?" or something like that. Instead, he's the silent presence.
I could have seen Travis with some below decks characters as well, even briefly - "Hiya, Sue, you going to Movie Night?" or something like that. Instead, he's the silent presence.