Adrienne Frost is the older sister of a fictional character that first appeared in Uncanny X-Men #129 in January of what year?
Adrienne Frost:  She is the older sister of Emma Frost and Cordelia Frost, but not much is known about her past. Emma Frost: Emma Grace Frost is a fictional character appearing in American comic books published by Marvel Comics, most commonly in association with the X-Men. Emma Frost:  The character first appeared in "Uncanny X-Men" #129 (January 1980), and was created by writer Chris Claremont and artist/co-writer John Byrne.
1980