Summer B. Lonns

 is a member of French Fireside Girl Troop 21212. Like Rosie, she lived in America but moved to France recently. Unlike Rosie, she wasn't part of the Fireside Girls until she moved to France. Her name is a pun on Summer Belongs to You, but without the "To You".

Rosie
Summer was Rosie's neighbor until they moved next door to Isabella. She was very close to Rosie and was sad when they moved, but met her again when they both moved to France. She joined Troop 21212 in order to hang out with Rosie more often.

Colette
Summer is also close to Colette, often making Josette and Rosie jealous, however, they only hang out off and on.

Canella
Summer is close to Canella, but only because she's troop leader and Summer wanted the "Friends with Leader Patch". They are friends, however.

Appearances

 * Toy to the World (First Appearance)
 * De Plane! De Plane! (Cameo)
 * France Field Trip (Phineas and Ferb: School Days), (First Speaking Appearance)