Lord knows what great-great-great-great-grandcollie's in the picture, but that's Lassie's mom, June Lockhart, who turns 85 today. We'll do the math: that's slightly over 12 in dog years.
The photo was taken last August at a ceremony for the issuance of "Early TV Memories" commemorative postage stamps. Only Lassie appears on the stamp. The bitch.
(It appears the current "Lassie" is a tenth-generation direct descendent from "Pal," who starred in the MGM films and the pilot of the TV series. Interesting article on Wikipedia.)
The official Lassie website notes that Lassie "doesn't meet the AKC standard for the breed. Lassie is bred larger than average so that a child actor can play opposite the dog for a longer time."
Another piece of trivia: "Lassie is a registered trademark, and that trademark requires the following: a sable and white collie, four white feet, a full white collar and a white blaze up the nose."