Name: Theresa "Terri" Cassidy
Code Name: Siryn
Father: Sean Cassidy aka Banshee
Mother: Maeve Cassidy
Age: 19
Birthplace: Cassidy Keep, County Mayo, Ireland
Height: 5'6"
Weight: 124 lbs
Eye Color: Sharp blue
Hair Color: Deep red gold and long, usually pulled back in a ponytail with a few locks framing her face.

Mutation: Terri inherited sonic and minor psionic power from her father. Her screams can shatter any known substance (with the exception of adamantium and vibranium) and, ussed at lower intensities, can knock a person unconscious. Her powers also allow a form of flight (the accoustics are directed behind her by her psionic powers), buring which she can stop screaming for short periods of time to speak or attack, depending on the situation. Terris' psionics create a natural shield around her body when she is using her powers, and direct her acoustic blasts in any direction she desires.

History: Terri never knew her mother, and her father had no idea she existed for many years. Her mother died in an IRA bombing while Terri was an infant, and her father had never known his wife was pregnant, due to his work. Thought dead in that same bombing, Terri was found after the blast by her father's cousin Black Tom Cassidy (whom she called Uncle as a sign of respect), and was raised in a life of crime, although her heart wasn't in it.

After her powers emerged at puberty, Tom, also a mutant, escalated their criminal activities and gave her the codename Siryn. While in San Fransisco with her Uncle and his partner Juggernaut, Black Tom was captured. He exonerated her of all responsibility of the crimes they had commited together, and wrote a letter for her to give to Sean explaining who she was and where she had been for sixteen years. After several months of searching, they were finally reunited as a family.

She had never had to deal with anti-mutant factions, as all her uncle's contacts were mutants, and the terrorist organizations they worked for prefered mutants, as their powers could be used to further their goals. While in New York she ran into a mutant-hating faction for the first time, and interviened to try and stop their attack on another mutant. She succeeded only in getting herself shot.

Sean, worrying that his job as an Interpol agent left him little time to keep his daughter from harm's way, talked to her about inrolling in his friend Xavier's school for the gifted. And so, fresh out of the hospital (and somewhat bitter about the experience) she headed upstate to visit the school.