Question: Adrienne Frost is the older sister of a fictional character that first appeared in Uncanny X-Men #129 in January of what year?

Context paragraphs:
Adrienne Frost: Adrienne Frost is a fictional supervillain appearing in American comic books published by Marvel Comics.  The character appears in stories set in the Marvel Universe, commonly in association with the X-Men.  She is the older sister of Emma Frost and Cordelia Frost, but not much is known about her past.

Gambit (comics): Gambit (Remy Etienne LeBeau) is a fictional character appearing in American comic books published by Marvel Comics, commonly in association with the X-Men.  The character was created by writer Chris Claremont and artist Jim Lee.  Drawn by artist Mike Collins, Gambit makes his first appearances in "Uncanny X-Men Annual" #14 (July 1990) and "Uncanny X-Men" #266 (August 1990).

Graydon Creed: Graydon Creed is a fictional character appearing in American comic books published by Marvel Comics.  The character was created by writer Scott Lobdell and artist Brandon Peterson.  The character is an enemy of the X-Men and first appeared in "Uncanny X-Men" #299 (April 1993).

Morlocks (comics): The Morlocks are a group of mutant characters appearing in American comic books published by Marvel Comics.  The characters are usually depicted as being associated with the X-Men in the Marvel Universe.  Created by writer Chris Claremont and artist Paul Smith, they were named after the subterranean race of the same name in H. G. Wells' novel "The Time Machine".  They first appeared as a group in "Uncanny X-Men" #169 (May 1983).  Caliban appeared prior to that (in "Uncanny X-Men" #148), but he was not yet a member of the Morlocks.

Cable (comics): Cable (Nathan Summers) is a fictional character appearing in American comic books published by Marvel Comics, commonly in association with X-Force and the X-Men.  The character first appeared as a newborn infant in "Uncanny X-Men" #201 (Jan. 1986) created by writer Chris Claremont, while Cable's adult identity was created by writer Louise Simonson and artist/co-writer Rob Liefeld and first appeared in "The New Mutants" #87 (March 1990).

Days of Future Present: "Days of Future Present" is a storyline published by Marvel Comics, appearing in the 1990 annuals of "Fantastic Four", "X-Factor", "New Mutants" and "Uncanny X-Men".  Centered on the appearance of an adult version of the powerful mutant Franklin Richards, it is a sequel to the popular "Days of Future Past" story arc from "Uncanny X-Men" #141–142 (January–February 1981).  The storyline unites the Fantastic Four, X-Factor, the New Mutants, and the remnants of a then-disbanded X-Men against a common foe from a dystopian alternate future.  It features the first appearance of Gambit, and the first encounter between Jean Grey and her alternate future daughter Rachel Summers.  Cyclops' baby son Nathan Christopher Charles Summers and the full-grown mutant antihero Cable are depicted in this story as two separate individuals, although they are subsequently revealed to be one and the same.

Cerebro's X-Men: Cerebro's X-Men are a fictional team of supervillains appearing in American comic books published by Marvel Comics.  The characters appeared in both the "Uncanny X-Men" and "X-Men" series.  They were created and designed by Spanish artist Carlos Pacheco but he officially drew them just once in the cover of "Uncanny X-Men" No. 360 (1998).  The interior art of this issue was done by Chris Bachalo.

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.  The character first appeared in "Uncanny X-Men" #129 (January 1980), and was created by writer Chris Claremont and artist/co-writer John Byrne.  Emma Frost, also known as the White Queen, has evolved from a supervillain and foe of the X-Men, to becoming a superhero and one of the X-Men's most central members and leaders until the events of "Inhumans vs. X-Men".

Kitty Pryde: Katherine Anne "Kitty" Pryde is a fictional superhero appearing in American comic books published by Marvel Comics, commonly in association with the X-Men.  The character first appeared in "Uncanny X-Men" #129 (January 1980) and was co-created by writer-artist John Byrne and Chris Claremont.

Brood (comics): The Brood are a fictional race of insectoid, parasitic, extraterrestrial beings appearing in American comic books published by Marvel Comics, especially "Uncanny X-Men."  Created by writer Chris Claremont and artist Dave Cockrum, they first appeared in "Uncanny X-Men" #155 (March 1982).

Supporting paragraphs: Adrienne Frost Emma Frost
Answer: 1980