Question for Dear Deidre: "Help me! My little sister just comes and hugs me. But I can't stop being a bitch..."

Dear' Miss Manners;

I’m 15 and I have a sister aged nine. I love my sister, but my mom and I always seem to be fighting and arguing. My little sister just comes and hugs me and it makes me feel like a right horrible bitch.

I know I should be nice to her because I’m her older sister and she looks up to me...

Source: www.thesun.co.uk