[WVU alpha phi]

A girl in my pledge class was 25 (and a legacy to our chapter). She never truly fit it with the rest of us who were 18 and 19 year olds. After initiation when activities were no longer mandatory, she never came around and really didn't have any friends in the sorority. I think she was probably uncomfortable being so much older than the rest of us but had wanted to join anyway. She ended up transferring to a school in the Midwest the following year; no one that I know of has talked to her since.
If your friend wants to give recruitment a shot, best of luck to her. But I think she should seriously consider if she will fit in with younger girls.