Lara and her family own the Laramie Ranch, an area just outside of the Kanto Safari Zone. Lara and her Ponyta and Growlithe helps guard the ranch from Pokemon poachers.
Lara was going to enter a race with her Ponyta when Team Rocket, working for Dario, caused an accident that lead to her breaking her arm. Lara was saddened, but quickly realized that Ash could ride her Ponyta in the race.
Ash and Ponyta entered the race, and they were able to successfully defeat Dario, and all the other trainers, and win the race. In the process, Lara's Ponyta evolved into a Rapidash.