Young lovers, old friends ... Juliette Lewis and Brad Pitt had a relationship in the 1990s when she was in high school. Picture: Instagram Source: Supplied

Most recently seen in cinemas in August: Osage County, the 41-year-old actor shared a sweet throwback photo of herself and then-beau Pitt on the occasion of his 51st birthday.

The Instagram image was captioned with a grateful message: “HAPPY BIRTHDAY to my old friend. Who taught me so much as a wee youngster. And shaped a lot of my musical taste early on. I first heard the Pixies, John Lee Hooker, Gregg Allman, Nina Simone because of BP.”

Co-stars ... Brad Pitt and Juliette Lewis (back seat) with Michelle Forbes and David Duchovny in the 1993 film 'Kalifornia'. Source: News Corp Australia

She describes her Too Young to Die? and Kalifornia co-star as “always somewhat of a ‘dignified rebel’.”

Lewis was a teenager when she dated the now megastar. “It’s a lifetime away,” she reflected to a British newspaper in a 2010 interview. “I was in my high school years and it was a wonderful, loving relationship with a fun, smart guy. Then it was over and he went on to become incredibly famous.”

Parents of six ... Brad Pitt with wife Angelina Jolie at the premiere of Jolie’s directorial debut ‘Unbroken’. Picture: Ben Symons Source: Supplied

Pitt married actor Angelina Jolie, 39, in an intimate wedding in August at the chapel of Château Miraval, the family’s estate in the French village of Correns, with their six children in attendance.