Kid Brother tells the story of Aaron (Alan Longstreet), a sullen night janitor whose lonesome life gets shaken up with a surprise visit from his little brother, Jared (Peter Hérold). Hoping to reconnect with their estranged father, Jared enlists Aaron's reluctant assistance in filling in the gaps of his memory and attempting to discover their father's current whereabouts. Aaron's mundane life gets even more complicated when a chance encounter with a woman named Amanda (Tonya Hawkins) and a dropped phone number set in motion the makings of a hilariously awkward relationship. The trio could not be more different, and yet as they come together to cope with their pasts and confront their presents, they learn that sometimes a little shaking up can be a good thing. And as the brothers learn to connect again, they find that, despite their many differences, family is family.