This is a fairly random idea that poped into my head that may not work
please enjoy. By the way the Jacksons and Smelly gabe are fairly rich so the can aford stuff

Chapter One
My name is Penny Potter, but im often called Penny Jackson. I am a year older than my brother Harry Potter. I am a witch and a demigod. My mother Lily Potter and father James Potter thought it best not to tell people about me because of my real father. So I was raised by Sally Jackson she is really loving. My story starts when I turned 11.

"Penny, wake up!" Sally called from outside my room, "Gabe is gone for the day, we can do anything you want!"
I poked my head out the door, "Anything?" Sally nodded, I did my signature happy squeal. "Can we bake a birthday cake?"
"Yes honey." Sally answered. I ran to the kitchen and pulled out a box of cake mix and twenty minutes later we were laughing and icing the cake. I had manedged to drop an egg on the floor and get frosting on my forehead. Once we finished we put the cake in the microwave to cool. We waited Anouther ten minutes and pulled out the cake and plates. I had just blown out my candles and was about to cut my cake when an owl swooped through the open window and dropped a hevey yellowish parchment on top of my cake. I picked up the envelope and read the address, it said Penny Jackson, third room on the left, apartment 32, 9182 Central Street, Manhattan NY. I turned it over and opened the envelope. "What is it honey" Sally said.
"It's an invitation to a school called Hogwarts!" I said.
" Do you want to go?"
"Ya I guess so."
"Well Lily told me about this school we need to go get school supplies from London. We should take a boat it will be fun and i'll come with you and stay till September first when school starts. Now lets finish the cake and try not to taste parchment." I laughed and finished cutting the slices of cake. "Cut one for Gabe too honey." Once we finished the cake we wrapped the cake in plastic and cleaned up the floor and the rest of the kitchen. After cleaning we sit down and start watching H2O.
" I home!" Gabe calls unlovingly from the frount door.
"We made cake!" I called, I think my mother thinks im to happy twords him or most people and trusting. "I also found a new school, in Kings Cross England."
"In England how are you going to get there?" Gabe said rudly
"We are taking a boat there, and i'll take a plane back and be back by september third."
"What am I supposted to eat!" Gabe talk yelled fustrated
" I'll put take out numbers on the fridge and some restaurant names if you want to eat out." Sally told him sweetly.
"OK but be back soon i don't want take out for the rest of my life."
"Um Gabe we are going to need a little more money for school supplies." I told him nervously.
"Fine but don't ask for more!" He said exasperatedly, thrusting a wad of bills into my hand.
"Honey, go pack your thing we are leaving first thing tomorrow!" Sally siad.
" Yay I can't wait I don't think I'll get expelled from this school!"

ok i admit Gabe is Probably ooc but im not sure how to right him and i think i kinda like my gabe virsion