My mistake( mortal instruments fanfic)

Not a very happy family

Alexia's POV
I took a deep breathe very quickly. Clarissa had just told me and Alex that Jace was our father. I walked up to Jace and Clarissa and punched them both right in the face almost breaking there noses while doing it. I was never a very polite child so I don't tend to show that I am.
"Alexia" Rissa and the others yelled at me.
"Yes" I said sweetly.
"Get back here right now" They all shouted. Very loudly I might add. Deciding to be a good girl I went back to them.
"Yep" I said not popping the 'p'.
"What is up with you and hurting people?" Isabelle and Alec asked. Turns out there brother and sister.
"I don't know it's in my blood" I said smirking then I realised who my blood was and stopped smirking. They all looked over at Jace with a knowing look.
"Right I'm gonna go now" I said before sprinting off again.
"Really Alexia you are making me run" I heard Alex and Rissa say together. Ahhhhh such a cute couple. Gotta get them together some day but right now gotta run. I haven't been here since I was little so I had no idea where I was going.
"Ahhhhhh" A masculine voice said. Since I wasn't looking were I was going I ran into someone. The person I ran into grabbed my arm and pulled me into a room.
"Woah dude just cause I ran onto you doesn't mean I want to have sex with you" I rushed as he put his ear to the door. He had dark brown hair and light blue eyes to match. He reminded me of Alec and Isabelle.
"I don't want to have sex with you either" He said while turning to look a me.
"I'm Dallas Lightwood" The boy said while sticking his hand out to shake. I ignored it .
"I'm Alexia but you can call me whatever and did you say Lightwood" I said. He said Lightwood so he may be related to Alec and Isabelle.
"Yeah, Isabelle and Alec are my cousins" Dallas said. That makes sense.
"Alexia" I heard the amazing couple shout together.
"Alex, Rissa" I shouted back.
"We just want to talk" Alex said coming up to the door I was now leaning on and knocking on it.
"That's what they say in the movies then they kill them" I said trying to hold in my laugh.
"Uncle Dallas can you get her out please" Rissa said. I glared at Dallas before running to the other side of the room.
"Are you a naughty girl?" Dallas asked amused.
"The worst" I smirked.
"That's my taste in girls" Dallas chuckled.
"I don't care" I shouted as I ran out of the room and straight past Alex and Rissa. I heard them both groan as they saw me running.