Gaby is Jutta Mueller's daughter. She was Peggy Fleming's international rival in 1968. Peggy got first in both phases of the 1968 Olympics while Gaby got 2nd in both phases. It's interesting to note that at that time Peggy and Gaby where still able to beat Trixie Schuba in compulsory figures, who placed 3rd in compulsory figures but 12th in free skating.
I will point out that I admire Trixie Schuba's compulsory figures now and I think they were the greatest ever, including among all the men skaters.
Also, it is a foregone conclusion that Annette and Katarina were modeled after Gabby ... Errr ... and Coach Jutta Mueller actually poached Annette from coach Gabby Seyfert