In the season 2 official trailer, it showed a brief clip of Jimmy and Stephanie sharing a kiss outside of the Fuller Home, only to show Kimmy walking out saying, "Jimmy!". Jimmy and Kimmy then hug while Stephanie looks at them both, confused as both Kimmy and Jimmy do the 'Gibbler Gallop'. Kimmy then tells Stephanie that this is her little brother, Jimmy. Stephanie replies, "I just kissed a Gibbler?". Kimmy looks at Jimmy, disgusted and says, "You just kissed a Tanner?!". Stephanie and Kimmy both look at eachother and say, "Ew!".
After he has his second kiss with Stephanie in season 2 episode 2, it is revealed that they are dating.
Jimmy is shown to be tall and very handsome. His clothing style is casual, usually wearing long sleeved shirts and jeans. He has a bulky build, he is very muscular, he has an immense chest shown to create outlines on his shirt, and his athletic, massive biceps are noticeable when he is in T shirts. His hefty build is what attracted Stephanie at first.