Sister?

Luke quickly stood and accepted the envelope from him. His heart was racing like a fast car, the tension kept surging as he opened the envelope.

Before looking at them, he closed his eyes took a deep breath and tried to calm himself. When he felt calm enough, he opened his eyes and looked at them.

"Oh my God!" He screamed as he sank in the chair on seeing the results.

His scream was so girly that the nurse passing by outside of his door thought the doctor was treating a little girl inside. Inside the office where no little girl was, Luke's heart had picked up pace again. 

Possibility of relationship is 50%

Luke kept reading the statement over and over again. Suspecting that he and Phoebe were actually related was one thing but actually confirming it was another. He mulled over what to do next and had so many questions running through his mind.