In 1985, Linda Gray should have felt on top of the world.

After fighting for the chance to direct an episode of her hit show Dallas, on which she played Sue Ellen Ewing, the often-drunk, dramatic wife of conniving oil baron J.R., she had won her shot.

linda gray 'dallas'

Linda and her Dallas costar Larry Hagman in 1981.

The night before filming began, she recalls, “I was sitting on the bed surrounded by papers and the phone rang. It was my sister.” Linda was stressed out and distracted, but when Betty Gray called, she picked up. “She was four years younger and we were like two peas in a pod,” Linda tells Closer. “I thought she was calling to say, ‘Good luck tomorrow.’”

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But her little sister had bad news: “She was calling to tell me she had just been diagnosed with breast cancer.” Tragedy has chased triumph throughout Linda’s life. Her sister’s death in 1989 at 43 “was a huge turning point,” she says. “I realized the fragility of life and how fast it goes.”

linda gray and betty gray

Linda and her sister Betty in January 1987.

After the heartbreaking jolt of losing Betty, Linda, who turns 75 on Sept. 12, vowed to appreciate each step of her life’s journey. “I’m excited about life every day,” she says. “The minute my feet touch the ground in the morning, I say, ‘Thank you.’”

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Now she’s sharing her hard-won truths in a new book, The Road to Happiness Is Always Under Construction. “I’ve had tragedy. I’ve had things go on in my life like every person. It’s how you deal with them that propels you forward.”

To read the full story on Linda, pick up the new issue of Closer Weekly, on newsstands now!