Harry James Potter and Elisabeth Lily Potter.
Disclaimer: I do not own Harry potter or any of the characters; I only made up Elisabeth Lily Potter.
A/N Harry is 17 and discovers that he has a 19 year old sister.
Harry's parents died while he was 3 and she was 5.
Oh by the way I'm from Holland so there may be spelling errors.
Harry was in his dorm unpacking his trunk, as he just had arrived from the station after a lengthened holiday. He had been sick, at least that is what he had told his teachers. He head been thrown down the stairs by his uncle five weeks before the start of term so he had broken his leg, at least aunt Petunia had taken him to the hospital behind her husbands back, so he had arrived a week later than the rest of the school.
He was just putting his cloak on to go to Professor McGonagall to pick up his schedule, when he realized he wasn't due to pick it up for another hour.
So he took his cloak off and hung it back in his closet.
He walked to his trunk and took the present for Ron a new robe for parties out of his trunk and placed it on Ron's bed.
When he turned around he jumped in surprise his headmaster was standing in the middle of his dormitory.
"Hello Professor Dumbledore." Said Harry "Wait, Why are you here? I mean you never come into our house unless there's something terribly wrong."
"Well in this case I have some excellent news I have found a relative of you, which is closer to you than your aunt and uncle, fortunately she's 19." Dumbledore answered with that well know twinkle in his eyes.
"Who is she?" Harry asked.
"Elizabeth Lily Potter." Was the answer.
"Wait Lily as in my mom and Potter as in my dad?"
"Correct she is your sister and unlike you she can recall everything as soon her memory locks are removed."
"Wow, wait, hold on, rewind SISTER?" Harry said in shock as his legs gave way luckily he was standing next to his bed so he landed on his bed.
Ron who walked into the room and towards his bed and said: "Oh hello Professor Dumbledore, hi Harry, wait a sec professor!"
Ron looked back and saw Harry's white face and asked: "hey Harry you alright, you look awful. Is everything alright or should I get Madam Pomfrey? "
"What... Yeah... No... just ..." stuttered Harry.
Dumbledore said: "No that won't be necessary Ron, Harry's alright; I just told Harry something that shocked him."
"And you call it alright when he's in shock." Ron said sarcastically.
"Well it's perfectly understandable that he's in shock because I have just told him he has a 19-year old sister called Elizabeth Lily Potter. She has been in a orphanage since her sixth year because her parents where killed then and she hasn't come looking for Harry because she has about four memory locks that keeps her from remembering him.
I found her because some death eaters were terrorising the neighbourhood and were heading straight for the orphanage she lives.
She came outside and blasted them into the next street out of pure panic that they would kill her best friend.
Although I gave Harry the shorter version but since he's sitting there he should have heard that."
"Yeah I see what you mean I would be shocked too."
"Where is she now?" Harry's question came suddenly.
"St. Mungo's to have those memory locks removed, and to have some minor injuries healed."
"I want to see her." He said while he walked to his closet and got his cloak.
"I was getting you to do just that." Said Dumbledore
"But I want Hermione and Ron to come" said Harry.
"I'll go get her." Said Ron as he jumped trough the door.
"Alas I could have seen that one coming seeing as you three are always together."
"Yes you could have." Said Harry as he left the room.
Dumbledore closed Harry's trunk and closet and exited the room also.
He found Harry, Hermione and Ron amidst of whole Gryffindor house who expected an answer from the three prefects.
"Not now okay I'll explain later." He heard Harry say to the rest of the Quidditch team from which he was captain.
"Ready Harry?" he asked
"Yes Professor." Harry answered
"Ready for what Harry?" asked Ginny.
"Ron an I'll will fill you in later Ginny." Harry said after which he followed the others who had already exited through the portrait hole to find the entire school assembled there.
"I don't have time for this." Harry said looking determined and with a glow in his eyes that scared the first row of students so they backed out of the way.
"Students return to your houses." Dumbledore said loudly.
The students groaned but did as they were told and dispersed to their own common rooms.
"Where's Harry?" asked Hermione.
"Probably near the borders of our terrain by now." Dumbledore answered dryly.
"What! Come on Ron we have to go after him." Hermione exclaimed.
They started to walk toward the main staircase in a hurry to catch up with Harry.
They finally caught up with him in front of the great hall.
"Finally come on let's go already." He said impatiently.
"Easy Potter take it steady or you'll get stuck when you try to apparate."
"Like I would care." Harry said angry.
"Harry you can't seriously mean that." Hermione said shocked.
"And why can't I?" he asked.
Harry started to walk faster towards the edge of the terrain where he apparated to St. Mungo's where he had already been once.
"Bloody hell what does he think he's doing."
"He's angry can't you tell. This is what... the 30ste time he hasn't been told something about himself." Hermione said irritated
"Well quite right, but let's go already." Dumbledore said impatiently.