Making Sis Feel Better

When I was 14 I was a pretty trustworthy kid. I made good grades, stayed out of trouble, and overall pleased my dad and step mom. Most of the time when they went out of town they would call my grandmother to come up and sit at the house with me, my brother, and my step sister. This weekend however, they decided that since my brother had just turned 18 he was more than capable of watching us.
My brother, Todd, was no doubt the trouble maker of the 3 kids. As soon as our parents left he informed me that he would be leaving to go stay with his friends in the city. For a small sum of money I agreed to keep my mouth shut; we lived in the country, nothing ever happened. Todd left and me and Tiff had the house to ourselves.
Tiff had just turned 12 and was starting to blossom. She was rather thin, with strawberry blonde hair and a fairly light complexion. I asked her “What do you want to do?” since we couldn’t go anywhere, being I was only 14 and had no license. She replied, “I’m really hungry, you should throw a pizza in the oven.” I had not eaten since early that morning and was starving as well. So I cooked dinner, we watched some TV, and rented a pay per view movie. Just a nice quiet night with nothing out of the ordinary.
About half way through the movie I hit pause on the DVR and called “Bathroom break!. ”
“Thank God!” Tiff replied, and hurried to the bathroom.
I had to pee really bad so I decided not to wait and walked outside to pee off of the back porch. For a 14 year old I had an averaged size dick, about 5 inches rock hard. I hated the way public hair looked as soon as it started sprouting when I was 12 so I kept myself well shaved. I walked back inside to find Tiff had not yet returned from the bathroom so I went to the kitchen to fix myself a drink for the rest of the movie.
Ten minutes later Tiff had still not come out of the bathroom, so I walked to the bathroom door, knocked, and asked “Are you alright in there?”
“That pizza isn’t sitting to well with my stomach.” She replied
“Alright” I said, “Do you need anything?”
“No, I’m fine.” She retorted, so I went and hit the record button so she could go back and watch any parts she missed.
After the movie finished I noticed she still had not come out of the bathroom. Once again I went to the door to check on her.
“Do you need some medicine?” I asked, trying to be a good big brother.
“I don’t think I can get off of here without making a mess!”
“Well just unlock the door that goes into your room and I will bring you some.” I said, our bathroom had two doors, one leading to the hallway and the other into her bedroom.