Caitlin was born in Unova, and at a young age, moved to Sinnoh with her family. She tapped into her Psychic abilities upon arriving in Sinnoh, and has ever since trained to become a Psychic-type Master, eventually becoming the leader of the Battle Castle. Not being interested in battling when she was younger, Caitlin employed Darach to battle for her, after receiving her title. A few years later, Caitlin had an accident which resulted in her wanting to begin battling. She then left the Battle Castle and headed back to Unova, where she became a member of the Elite Four.
The Alexis Saga
Caitlin first appeared in Best Wishes where she joined the group while exploring the Dreamyard. During her time, she captured a Gothita, Solosis and a Pawniard, in which the former two evolved fully into Gothitelle and Reuniclus respectively. She also took part in the Musical Contest held in Unova, in which she reached the final and eventually won the contest. She left the group for unknown circumstances at the same time, before returning as a member of the Elite Four, something that Caitlin hadn't mentioned. She and Alexis battled until Caitlin was ultimately defeated.
Her second appearance saw her return in Battle Frontier for Alexis's Battle Frontier Challenge, wanting to witness Darach's battling skills now since she left the Frontier. She eventually left the team once they returned to Unova and her Pawniard had evolved.
She briefly returned Alexis returned to battle the Unova League two years later, where she was once again defeated.
Caitlin had a large role in both M03 and M04 in taking down the Ghetsis Initiative.
This listing is of Caitlin's known Pokémon in the anime:
Munna is a Pokémon caught by Caitlin. Munna was the first Pokémon Caitlin obtained in the Unova region, after it's personality matched Caitlin's. It's is a laid back Pokémon that battles well but often snubs it's opponents outside of battle. It enjoys participating in contests more than battling, and has been Caitlin's token Pokémon for contests. It is unknown if she evolved Munna into Musharna.
Reuniclus was first caught as a Solosis by Caitlin. Solosis was a very quiet and reserved Pokémon when first caught, but learned to come out of it's shell more as it spent more time with Caitlin's team. When it first evolved into Duosion, it found it hard to adapt to it's new power, being afraid to attack. As it got over it's fears, it evolved once again into Reuniclus, this time being confident and powerful.
Bisharp was first caught as a Pawniard by Caitlin. It's a confident and brash Pokémon, that spends a lot of it's time battling and training for contests. It seems to enjoy participating in contests more than battling, using it's charm infused with it's strength.
Gothitelle was originally caught as a Gothita by Caitlin. Gohita was a boistrous Pokémon that spent a lot of time outside it's Pokéball. It evolved twice during it's time on Caitlin's team, however, was released by Caitlin after it desired to remain on Skyarrow Bridge.
This listing is of Caitlin's Pokémon exclusively for her Gym battles: