Jackson "Jack" Bartlett, aka "Grampa" or "GG", is the glue that holds Heartland together. He's an ex-rodeo cowboy and cattle rancher. The last thing he expected was raising a teenager again during his golden years.
Jack was born and raised at Heartland, back when it was a working cattle ranch. He would help his grandfather around the ranch as much as he could. promised to his grandfather to hold onto Heartland, all 600 acres. He spent years on the rodeo circuit, getting dozens of buckles and is considered a legend.
Jack and Lisa call it "quits" after his heart attack when she buys him a hospital bed for his convalescence and he hates it. Chastened, Lisa walks out of his life and returns to France, seemingly permanently. This incident is revealed only several months after it occurred, with Jack having morose flashbacks to their happier times, leaving viewers wondering about the status of their relationship in the meantime.
When Lisa returns in Episode 713 to ostensibly sell Fairfield and move to France for good, they have a few awkward meetings (one orchestrated by Tim).
After a road trip to Montana to deliver a horse to a new owner results in Jack and Lisa getting lost in the woods, the two find a way to reconcile.
They elope in the last episode of the season. When Tim shows up before the wedding, he is forced to keep it a secret until they choose to reveal this to the rest of the family.
Amy gets worried about Ty because he is in hospital when she is 9 months pregnant. Ty gets bailed from the hospital by Caleb to be his best man. Amy's water breaks in the limo on the way to Caleb's and Cassandra's wedding. Ty and Amy go back to their loft and Amy gives birth to a baby girl.