"Yes, she looks like me. NO— she is not my twin— she is my YOUNGER sister," I have to constantly tell people when Sarah and I are together.

I was blessed, (only now that I am not living in the house any longer do I think of it that way), with three younger sisters and one brother. Sarah is the closest to me in age.

This past weekend was the first time she has been able to come to campus to visit me. After seventeen years of sharing a room with her, secrets every night with her, a year of sharing a car with her, and millions of minutes spent fighting with her, I actually miss her at college (or maybe it's just her clothes). Either way, I was excited for her to visit me and to be able to share my life here with her (not to mention, take her to some parties).

My mom called the night my sister arrived with some last minute advice, worried to think of what two of her daughters could do together.

"Remember, the money I sent with Sarah is not to buy beer," my mom said as I rolled my eyes at my grinning sister. We had a whole weekend ahead of us.

But by Friday night, my nerves were already worn with my sister. She had come ready to shop. We had spent the whole day at the mall, she had already called her boyfriend twice, and it was getting harder to convince her to let me borrow her clothes. After shopping all day again on Saturday in Chicago, (we had to find the perfect prom dress for Sarah), I was exhausted. Especially at the thought of all my studying and homework I still had to get done.

It's stressful bringing someone from "outside" of campus into your life on campus. College life is already so incredibly busy and you just want that other person to fit perfectly into your daily routine of classes and friendships and to love your college as much as you do. Although I don't exactly know how I would feel if Sarah came to college here, I at least wanted her to want to come here. I wanted her to think I was a "cool" big sister and wish to be like me.

During one of our "arguments," (you couldn't expect us to go a whole weekend without one, could you?) I discovered how much Sarah hates being compared to me. I never thought it was such a big deal until she mentioned it this weekend. She complained of how she always felt she was being measured up to me. It's funny because we're not even alike. That's one of the reasons I like her, because she's not like me. Do you remember when you were younger how you always had to say to other kids, "Stop copying me?" We didn't want anyone else to steal our ideas then. Those ideas helped mold us into the young adults we are today. We don't want to lose our identity.

As we grow older (and more tolerant of each other) my respect for my little sister grows. She is not only my sister, but also my confidant, and always has a new wardrobe for me to wear.

• Sharing my sister's identity