How old was John Travolta in the movie Grease

It's been a whopping 44 years since Grease first roared to worldwide success, cementing it as one of the biggest and best loved musicals ever.

This week brought the tragic news that Dame Olivia Newton-John, best known for starring in Grease as Sandy, died aged 73 after a 30 year battle with breast cancer.

The singer and actress, who was born in Cambridge and raised in Australia, died "peacefully" at her Ranch in Southern California on Monday, surrounded by family and friends, her husband, John Easterling has said.

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Tributes have flocked in from celebrity friends, as well as her millions of fans. John Travolta, who played her co-star Danny in the hit film, said the late actress and campaigner had "made all of our lives so much better".

With so many people being affected by the news, many of us are watching Grease again, to re-witness Olivia's brilliance in all its glory. And with so much time having passed since its release, we've taken a look at where the rest of the cast are now, and what they've been up to since 1978.

John Travolta (Danny)

How old was John Travolta in the movie Grease

John Travolta in 2020 (Image: Sarah Morris/Getty Images)

A household name already, John had his breakthrough role with Saturday Night Fever in 1977 before playing T-Bird hunk Danny in Grease. Since then, he has become one of Hollywood's biggest stars, with roles in iconic movies such as Carrie, Pulp Fiction and Get Shorty.

More recently, he won acclaim for his role as lawyer Robert Shapiro in the TV drama The People vs. OJ Simpson: American Crime Story. He also recently reunited with Olivia Newton-John for a Christmas album.

John also has a great singing voice, and released a top 10 hit in 1976. His duet You're The One That I Want with Olivia-Newton John from the Grease soundtrack also peaked at number one following the film's release.

Born on 18 February, 1954, John is now 68 - and was 23 during the filming of Grease.

Stockard Channing (Rizzo)

How old was John Travolta in the movie Grease

Stockard Channing as Rizzo in Grease

Pink Lady Rizzo will probably be her most iconic role, but Stockard Channing had a hugely successful acting career after Grease. Her performance in Six Degrees of Separation, alongside Will Smith and Donald Sutherland, saw her nominated for an Oscar.

And she's also won an Emmy and a Tony award. Stockard famously played First Lady Abbey Bartlet in The West Wing for a number of years, and more recently appeared in The Good Wife.

She is also a regular on Broadway, and the West End. on February 13, 1944, Stockard is now 78 - and was 33 when she filmed Grease.

Jeff Conaway (Kenickie)

How old was John Travolta in the movie Grease

Kenickie actor Jeff Conaway in 2009 (Image: Michael Bezjian/WireImage)

Jeff actually played Danny in the original stage version of Grease, while John Travolta played Doody. Jeff later found TV success in shows such as Taxi and Happy Days.

Most of his acting career saw him working in television, as well as having a go at TV writing. He suffered from various issues with addiction, and appeared on various reality TV shows.

In 2011, he died at the age of 60 after contracting pneumonia. At one point, Jeff was married to Olivia Newton-John's older sister, Rona, for five years.

Born on October 5, 1950, Jeff was 26 when he filmed Grease.

Didi Conn (Frenchy)

How old was John Travolta in the movie Grease

Didi Conn ahead of Dancing on Ice in 2019 (Image: Jeff Spicer/PA Wire)

Didi Conn is best known for her iconic role that saw her rocking an incredibly pink hairdo. She also starred in the second Grease movie and had roles in Benson and Shining Time Station.

Although she didn't have many roles in movies, the actress took part in over 40 television series. Shows included Law & Order: Special Victims Unit, Rugrats, The World Thornberrys and Blue Bloods.

In 2019, the star made a surprise appearance as a contestant on ITV's Dancing on Ice.

Born on July, 13, 1951, Didi was 26 when Grease was filmed.

Barry Pearl (Doody)

How old was John Travolta in the movie Grease

Doody actor Barry Pearl in 2018 (Image: Jon Kopaloff/FilmMagic)

Barry Pearl is well-known for his iconic role as Doody, but he originally played Sonny in the stage version of the movie. He went on to star in the likes of Murder She Wrote, Beverly Hills 90210, House and ER.

The actor most recently appeared in Grease: Live in 2016. During the summers, he also teaches film arts across the US to the special needs community, the Mirror reports.

Born on March, 29, 1950, Barry was 27 when Grease was filmed.

Michael Tucci (Sonny)

How old was John Travolta in the movie Grease

Michael Tucci reprised his role for Grease: After They Were Famous, in 2002 (Image: YTV)

Fans remember Michael Tucci from his role as Sonny in the film. His career didn't end there as he went on to star in Barney Miller, Trapper John, M.D., The Paper Chase, It's Garry Shandling's Show, and Flying Blind.

Michael also got a regular role alongside Dick Van Dyke in Diagnosis Murder. Michael was also cast as Melissa McCarthy's father in the hilarious comedy The Heat in 2013. His most recent role is as Weezi Abramowitz in The Rich & The Ruthless.

Born on April 15, 1946, Michael was 31 during the filming of Grease.

Jamie Donnelly (Jan)

How old was John Travolta in the movie Grease

Jamie Donnelly as Jan (Image: CBS via Getty Images)

Jamie played Jan, one of the Pink Ladies. She was the only person to reprise her stage character in the film. She continued to act after the movie's release, starring in Family Affair for a few episodes in 2002 as well as Ray Donovan in 2014.

Her most recent acting credits include Violet in Cargo (2017) and Mrs Decker in The Waitress (2016). Born on May, 8, 1947, Jamie was 30 when Grease was filmed.

How old were the cast of Grease during filming?

John Travolta was 23 at the time that he played 18-year-old Danny Zuko, while Newton-John was 29 – more than 10 years older than Sandy, who was written to be 17 or 18 years old. Stockard Channing, who played Rizzo, the leader of the Pink Ladies, was 33 at the time of filming, making her the oldest of the main cast.

How old was John Travolta when he done Grease?

Olivia was 28-years-old and John was 23-years-old when they filmed Grease and the pair were on the edge of superstardom while shooting the movie.

How old was Danny Zuko in Grease?

Danny Zuko is 18 during his senior year at Rydell High School. The film "Grease" is based on a 1971 musical of the same name. It focuses on the relationship of American high school student Danny Zuko and Australian vacationer Sandy Olsson, who fall in love during the summer but fear they won't see each other again.

How old was Sandy in Grease in real life?

Olivia Newton-John, who on Monday aged 73, reportedly worried she was 'too old' to play the part of high school student Sandy Olsson in 1983 movie musical Grease. But the actress, who was 29 when she was cast as the fresh-faced teenager, is far from the only star to have played a much younger character on screen.