My older sister and I have had a great relationship, once we both managed to age out of high school. It wasn't that we hated each other as children, but 7+ years in age difference, along with me being very much an extrovert and she being an introvert, meant we clashed a lot. Of course, being that I was significantly younger than she, I was mostly on the losing end of our confrontations.
As I got older and our relationship improved, our fighting became good-natured picking on one anohter. One of my favorite delights was to be in some part of the planet that was quite lovely, which I just happened to know that she wanted to visit but hadn't, and call her collect from there. Yes, I did this quite a few times.
This particular time, I happened to be in Key West, FL for the afternoon (having driven down from Miami and back). As the group I was with were packing up to start the drive back, I noticed that there was a phone booth in the gas staion parking lot. Hello, I'll be right back; got to make a phone call. Don't leave without me.
Yes, I'm sure she rolled her eyes at my (still admittedly somewhat childish behavior), but I'm also sure she thought it cute that her college age brother thought enough of her to at least call and tell her hello from exotic places.
Now that we're even older, its more a text message or if I'm really feeling snotty, a Facebook post with her tagged in it, so other people can get in on the fun.