One of my friends got married in May. I was MOH in her wedding. Several guests (on the grooms side) came up to me and said they had no idea Bride had a sister, and how wonderful it was that I could attend the wedding. Bride and I have been friends since we were on the same little league team (so elementary school).
When Bride and I were around 19/20 years old, we went out to dinner with her boyfriend. He was 17 or 18 years older than us. We were sitting there, enjoying our meals, when a woman approached us, put one hand on my shoulder, the other on Bride's shoulder, and said it did her heart good to see two young ladies out having dinner with their Daddy, that so few kids are willing to be seen with their parents, and so on. When her boyfriend corrected the woman, and said that he was dating Bride, she got this look of absolute horror on her face. I guess she thought we were minors, and was horrified at the thought of a literal kid being involved romantically with someone so much older.