No she isn't, first it is Mona then it is the real Ali. Look up Pretty Little Liars on Wikipedia, it tells you everything!
The Jenna Thing is when, at the beginning of Flawless, Spencer, Ali, Emily, Hanna and Aria are having a sleepover and they catch Toby Cavanaugh spying on them. Ali decides to go into Toby's treehouse and set off fireworks to scare him. But, when she's in the treehouse, she sees Toby raping Jenna and sets off the fireworks at the wrong time, making Jenna blind. Toby threatens to tell on Ali, but Ali says she'll tell on Toby... So yeah, that's the Jenna Thing.
Jenna has to deal with Toby as a step-brother but she secretly hates him. You may think that Ali just set off the fireworks, but that wasn't what happened. Ali saw Toby touching Jenna inappropriately. Ali was so surprised that she lit the firework by surprise. When the firetrucks came and everything was over and Jenna was rushed to the hospital, Toby approached Ali. He said "I know what you did and I'm going to tell." Ali shot back and told him that if he told that she had lit the firework, she would tell his parents that he had touched his step-sister.
The real name and surname of Newstar Jenna are Jenna Busch.
Keegan Allen
Jenna Cavanaugh was blinded after being hit in the face by a firework. Her brother, Toby, took the blame but everything but Jenna getting hurt had been set up by Jenna and Courtney. Courtney claims to have misaimed when she was caught by surprise to see Toby abusing (touching) Jenna. Jenna Cavanaugh was later killed by Alison.
It made her blind
Hey! His name is Toby Cavanaugh.
Jay Cavanaugh died in 2005.
Dave Cavanaugh died in 1981.
Jenna Cavanaugh is played by Tammin Sursok.
John R. Cavanaugh died in 2007.
John J. Cavanaugh died in 1979.
James M. Cavanaugh died in 1879.
Jenna Cavanaugh, the step-sister of Toby Covanaugh, was killed by a construction worker.
Lucille Cavanaugh died on July 13, 1983, in Carmel, California, USA.
Tammin Sursok but you may know her from Hannah Montana as Jacksons bi bi bikini model or Sianna