I was a 23 year old freshman when I became a colony member of Alpha Xi Delta. I didnt have the opportunity to be an 18 year old freshman - had to get that 4 years of military out of the way first. And even though I'm older than the next oldest sister by over 3 years, none of the girls treat me any different. They still respect me as a sister. The most depressing thing though, is we took on a new member this year who JUST celebrated her 18th birthday. Good lord, I'm 4 weeks shy of being 8 years older than her. Dig the knife a little deeper!
Now, I will say that when I colonized, we had a 35 year old single mom also colonize with us. She dropped before Installation, but I will say that with her, it was a burden, and a HUGE hassel. She wanted to be our mother, and not our sister. Everytime we made plans to do something it was always "I dont have time for that, I have a child at home..." and it was a huge pain in the ass to have to make plans around her child. We would have, and could have, worked with her, but she finally realized that her child was a bigger priority in her life than sorority (as it SHOULD have been) and she dropped. Fortunately, for the rest of us, the tension in the colony left with her. We actually began to feel like a sisterhood after that...