K.I.
I have an older sister (we are 2 yrs apart) and love it...loved it...will always love it! It was only the two of us growing up and I too wish I had tried to give my daughter a sister...just wasn't to keen of the idea of having 4:)!
My sister and I were very close growing up and only bickered while in High School, usually about me wanting to borrow her clothes but nothing significant!
To this day, if we fight, its over in less than an hour...and I talk to her every day on the phone and see her at least 2-3x a week, as we have chose to live in the same city while our kids grow up!