Billie Cassidy

Billie Cassidy (born Jenkins) is a witch and the youngest daughter born to Carl and Helen Jenkins. Billie is married to Julian Cassidy and mother of their two children, Aspen and Reed Cassidy.

Besides the basic powers of a witch, such as spell casting, potion making, to see and talk to the death scrying, Billie has the powers of Telekinesis and Projection. She is also one half of the "Ultimate Power". According to her mortal parents, her powers came from her maternal grandmother.

Early Life
Billie was born to Carl and Helen Jenkins around 1986. As a child, she maintained a healthy relationship with her older sister, Christy. However, at the age of five, Billie witnessed her sister get brutally kidnapped by someone who would eventually be revealed to be a demon called Reinhardt. Since this event, her parents never spoke of Christy or the incident ever again, as they thought that it was what was best for Billie.

Billie's mother told her that she and her sister inherited magic from their grandmother. As a result of this, the Triad hired Reinhardt to kidnap Christy, knowing that the sisters would eventually grow to be powerful witches with a bond through magic and blood similar to the Charmed Ones, and set things in motion for the two sets of sister witches to stand against each other.

Practicing Witchcraft
After the Charmed Ones faked their deaths, Paige was assigned a new charge, who often bothered her by calling for her all the time. When she finally caved in and confronted Billie, she discovered the girl didn't need her help, but rather her guidance. After Billie tried to solve a kidnapping by herself, the Charmed Ones were forced to reveal themselves and save Billie. They then had a deal which entailed Piper, Paige, and Phoebe teaching her magic and, in turn, Billie would pick up the demonic slack so the sisters could retain their mortal lives.

The sisters then let Billie stay in their home in order to help her become more skilled in witchcraft. Despite having many other things to deal with, from time to time, Paige would assist Billie with potion-making and instruct her in fighting demons. The vast majority of the knowledge she came to have was acquired from Leo, whom Paige enlisted to help Billie learn the true definitions and origins of magic, though she also had a tendency to find things out for herself as well. Besides this, she also studied the Warren Book of Shadows and eventually created her own.

As the months went on, Billie became an increasingly powerful witch, proving herself to be a rare magical talent. Her mental based powers eventually expanded into a new active power, Projection: a supremely coveted and rare ability that enables the possessor to manipulate reality. However, it took her some time to adjust to this power, because of her ignorance of how to control it and use it properly.

In fact, when she just only unknowingly developed this power, she actually turned her parents into assassins and nearly got herself killed in the process by them. However, with the help of the sisters, the Book of Shadows, and Leo, she became exceptionally skilled in her Craft and learned to thoroughly embrace her destiny of being a witch.

The Ultimate Battle
After turning Billie against the Charmed Ones, Christy brought her to Magic School, which at the time was taken over by demons. Once there, she met Dumain, a demon who she thought was an imaginary friend when she was younger, however he was working with Christy and The Triad to kill the sisters. Once she settled in, Dumain staged an elaborate plan to use incidents of the sister's past to convince both Billie and The Magical Community that the Charmed Ones had truly become selfish with their witchcraft, and Christy got Billie to take over the Manor thus leaving, Piper, Phoebe, and Paige to hide out in the Underworld and then eventually Phoebe's condo. Throughout her whole situation, despite being convinced that the sisters had become selfish, she was still reluctant to hurt them, and tried everything she could think of to keep from having to kill them. Even after accepting that she must, she admitted that she still didn't like it. The Triad suggests to Dumain that Billie and Christy summon the Hollow to kill the Charmed Ones, however two other demons were listening in on the conversation and they also happened to be working with the sisters. Summoning the Hollow takes a powerful force. Although the Charmed Ones were able to summon it themselves using The Power of Three, Piper and Leo's oldest son, as it would take "Charmed power" to summon it. Dumain shimmered to Victor Bennett's apartment where Wyatt and Chris were staying and convinced Wyatt that he was needed to help his mommy. Billie and Christy held hands with the young boy and combined their power with his in order to summon the Hollow. Once acquired, they stole Wyatt's powers so they'll be evenly matched with the Charmed Ones.

Billie and Christy faced off with the sisters who had also summoned the Hollow. During the battle, the manor was obliterated, additionally killing Christy, as well as Phoebe and Paige. Billie goes to Magic School and Dumain convinces her to use her projection power to send her back to Christy. However, she discovers that he's using her to go back to the Triad instead.

Billie projects herself back into the past at the Manor, just as the past Billie and Christy arrive. She warns them but past-Billie sends present-Billie flying into the wall with Telekinesis and goes on to fight. The battle starts to play out as before but then Piper arrives with Grams and her mother to cast a spell which drives the Hollow out of the five girls. Present-Billie and Piper merge with their past selves, time has caught up with itself. Billie and Christy then teleport out with a potion. Billie tries to convince Christy that they have been used by the Triad, but all Christy can think of is fulfilling her mission and killing the Charmed Ones. Billie then goes to the sisters for help and forgiveness. She projects back in time with the sisters to vanquish the Triad in the past and tries to convince Christy to stop her vendetta and come with her, though Christy hurls a fireball at her, causing Billie to telekinetically repel the fireball back at her in self-defense. Billie then breaks down and cries at her sister's death, as the sisters surround her.

Before Blessed
After the Ultimate Battle, Billie moved to Los Angeles where she met her husband, Julian while studying to be a teacher. Years laters, she moved out to San Francisco alongside her husband and had children.

Personality
Billie is very intelligent and ambitious. Although smart, she was still new to the craft and had a lot to learn. Because of this, she unknowingly began calling for her whitelighter Paige Matthews. At first, Billie had too much pride to accept Paige's help. Billie was a quick study because she was very eager to learn. She has a very good heart and soul, and is overall a great person, despite her poor decisions in the past. She is very much independent, but works well with others. She is also vastly loyal to her family and the Charmed Ones, and will do anything for both of them.

Powers and Abilities
Billie is a strong witch, and is half of the Ultimate Power along wither her sister Christy Jenkins. According to her mortal parents, her powers came from her maternal grandmother.

Basic Powers

 * Spell Casting: The ability to cast spells and perform rituals.
 * Potion Making: The ability to brew potions.
 * Scrying: The ability to locate magical beings or objects. Billie is the first known witch to use a computer and crystal instead of a normal map and crystal. She still uses this form of scrying, and has taught her children how to scry this way.
 * Mediumship: The ability to see and commune with spirits of the dead.

Active Powers

 * Telekinesis: The ability to move objects and beings with the power of one's mind alone. It can be channeled through the eyes or the hands. Billie had learned to master this power quickly, given she used it to enhance her natural acrobatic and martial arts talents so that she could perform flips and other gravity-defying maneuvers.
 * Projection: The ability to manipulate reality. It is channeled through imagination, high levels of emotions, and the will to let things happen.

Notes and Trivia

 * Despite possessing an immensely strong power and known as the Ultimate Power, she was still not considered powerful enough to go up against the Charmed Ones with Christy and required Wyatt's help to summon the Hollow.