Laddie

 is Jonny's exceptionally alert and intelligent dog that lives in Modoc in 2241.

Interactions with the player character
Laddie helps The Chosen One during the quest Jonny is missing. Find him and bring him home to Balthas Laddie joins the party as a temporary companion. He leads The Chosen One to the well in the center of town where you can find Jonny's BB Gun.You can tell Balthas that you found Jonny's BB Gun and that you believe Jonny is dead, or you can continue to the Jonny's in the Slag caves. Find a way to get Jonny back home to Balthas quest. Once in the caves Laddie will help you identify Jonny in the area where the kids are held by standing in front of him. You have to ask Vegeir if its alright to take Jonny home, he will permit you to take him provided that you completed the Deliver Slag message to Jo in Modoc quest. After you complete this quest Laddie will leave your party, you wont be able to recruit this character again. 

Appearances
appears in Fallout 2.

Behind The Scenes
Laddie is a reference to an episode of "The Simpsons" where Bart gets a new dog "Laddie", which itself is an obvious reference to Lassie.