Their blissful weeks strolling the streets of Paris and getting steamy by the water’s edge in sunny Italy left Jennifer Aniston with no doubt in her mind – she’ll spend the rest of her life with her gorgeous man Justin Theroux. And when the actress, 43, confided her joy to her beloved dad John Aniston, his answer was typical of the soap actor’s larger-than-life personality.

“You tell Justin to make sure he treats you right, because I can still throw a left hook if he steps out of line!” a friend says John teased, after first shedding a few tears of joy. Unlike Jen’s turbulent relationship with her mother Nancy, her relationship with 78-year-old John is especially close. Last week when John broke it to Jen that he was at “very high risk” of a second heart attack, Jen and Justin, 40, reacted by immediately putting their loose wedding plans into top gear, says the friend.

“Jen wants her dad to walk her down the aisle, and she has promised him that day will come ASAP,” the member of Jennifer’s inner circle, who has known her for 12 years, tells Woman’s Day. “When Justin and Jen began talking about getting married, they considered doing it in September. But over the last month she pushed things back to next April. Now she has put her plans for a September wedding back on track.”

Six years ago John Aniston narrowly survived a massive heart attack, and in the years since he has been living on a cocktail of prescription drugs to try to negate the effects of his lifestyle. “John is not one for salads and cranberry juice,” our source says. “When he met Justin last July, they went to his favourite restaurant, Delmonico’s Steak and Lobster House – and John had the surf and turf, five glasses of red, a tiramisu and most of a cheese board! He lives by the saying, ‘There’s no point living if you don’t feel alive’.”

Read more about Jen and Justin's wedding countdown in this week's Woman’s Day on sale Monday July 2, 2012.