a change in relationships.

Yesterday after school, I was doing my homework whenever I heard my little sister dart through the door downstairs from after school. I am usually not home when she arrives home from school, so I when I heard her come upstairs to her room, I went in to say hi and ask how her day was. Instead of a normal response of "it was good" I got a "get away!" This shocked me at first. My relationship with my little sister, Tatum, has always been close and tight, and I make sure that I am always there for her when she needs me to be. I wasn't sure what I did to deserve this answer, but it didn't feel good. The day before was her birthday and I gave her a special card and made sure I said it to her as soon as I saw her. However, I couldn't make it to her birthday dinner so I knew this gave her some kind of resentment towards me. I for some reason really hated when she was mad at me the most out of my siblings, probably because I want her to come to me and not remember me when she is older as pushing her away. I asked her what was wrong and she gave me rude remarks, so I left her alone. Instead of bothering her I felt it was better to leave her alone. She is getting older, considering that she just turned eight and is already in the third grade since she is the youngest. I remember going through that stage in my life and caring about friends more than anyone else so I understand where she is coming from. But I hate the change. I think the best way to deal with it is waiting for her to come around to me for another couple of days, and if not then I talk to her. But in general I feel like a lot of people have the same issue and it's not a good feeling whenever you don't want to be pushed away.