She's best known for portraying the iconic Pink Lady, Frenchy Facciano in Grease.And almost 50 years later, Didi has barely aged a day as she marked her 75th birthday on Monday.Didi was part of the ultimate group of bad girls, Rizzo, Jan and Marty, who 'acted cool, looked cool, and were cool', and helped wholesome Sandy Olsson unleash her wild side to snare Danny Zuko.Her bubbly and beauty-obsessed on-screen character has followed into her real life as she continues to follow an incredibly positive outlook on life.And she shows no signs of slowing down any time soon as she recently launched a new Laura Geller Beauty campaign, with a nostalgic nod to her Grease roots.The advert sees Didi clad in a pale pink dress as she plugs their products by musing: 'You might remember when I famously dropped out of beauty school. I thought my life and my hair was ruined and I'd have to spend eternity making expensive salon appointments.'Her youthful looks sparked an online frenzy from fans wondering how Didi has stayed looking so young over the years.As she marks another year older, how does the Pink Lady icon maintain her youthful looks? She's best known for portraying the iconic Pink Lady, Frenchy Facciano in Grease... and almost 50 years later, Didi has barely aged a day as she marked her 75th birthday on Monday Her bubbly and beauty-obsessed on-screen character has followed into her real life as she continues to follow an incredibly positive outlook on life (pictured in the 1978 movie) Didi was part of the ultimate group of bad girls, Rizzo, Jan and Marty (L-R Didi, Dinah Manoff, Stockard Channing and Jamie Donnelly)Didi credits her mother's genes for 'blessing' her with incredible skin, alongside her simple beauty regime.She stresses the importance of using a gentle cleanser with a warm towel before applying heaps of moisturiser. For makeup, Didi avoids heavy coverage and uses minimal eye liner, blush and a little lip stick. Botox or plastic surgery has never been a route Didi has wanted to go down - she instead prefers to age naturally.'It's putting something foreign into your face,' she told People. 'It scares me.' 'My mother had beautiful skin, and I have to say, I inherited her skin,' she added. 'I never had acne. She had just the softest, most beautiful skin, and as I got older, people said, "Oh, Didi, you look so great". Then I hit menopause and there was a pause to, "Didi, you look so great".'When it comes to her hair, Didi is all for keeping her greys covered thanks to Laura Geller's newest Root Touch Up product. Didi is also no doubt kept young by her positive attitude. 'I have so, so much to be grateful for, honestly', she told People magazine last month, before crediting her late co-star Olivia Newton-John for teaching her about gratitude.Didi then revealed that she secretly battled uterine cancer and underwent a hysterectomy a year and a half ago.In an interview with New Beauty last month, Didi revealed she had secretly battled uterine cancer and had a hysterectomy a year and a half ago.She began to suffer with drying skin after the operation and started to use Laura Geller Care's moisturizer.'Having the hysterectomy changed my estrogen in a way that you know, wrinkled up', she said. 'I go to my heart and gratitude, honestly, look at how fun this is to be talking to you about a product that is very useful.'While she appears incredibly confident and comfortable in her own skin, Didi says the ageing process sometimes gets to her.'I think as I got older, you know, one can get very self-conscious about how you look and the wrinkles, I mean, I'm still not quite used to it', Didi explained.Born as Edith Bernstein in Brooklyn, New York, Didi started acting in her early teen years.Didi revealed last month that she secretly battled uterine cancer and underwent a hysterectomy (pictured on Dancing On Ice in 2019) And she shows no signs of slowing down any time soon as she recently launched a new Laura Geller Beauty campaign, with a nostalgic nod to her Grease roots Her youthful looks sparked an online frenzy from fans wondering how Didi has stayed looking so young over the yearsShe rose to fame in the early '70s, landing a few small roles, but arguably her first major part was in the Grease, where she played Frenchy.And that was just the beginning for her. She was then cast in the popular sitcoms Benson and Shining Time Station, and returned to play Frenchy in Grease 2.Her other acting credits include the flick Almost Summer, the biographical drama Frida, comedy movie Most Likely to Murder, and The Mimic in 2020.She also voiced the popular cartoon character Raggedy Ann in the movie Raggedy Ann & Andy: A Musical Adventure.Didi had a cameo in the 2016 TV special Grease: Live, making her the only original cast member to appear in all three Grease movie adaptations.In addition to her acting, she is also a talented figure skater and participated in the eleventh season of British show Dancing on Ice in 2019 when she was 67, making her the oldest person ever to compete on the series.She married Frank Conn in 1975, but they divorced three years later, in 1978.Didi then tied the knot with acclaimed songwriter David Shire in 1984, and together, they welcomed one child together, a son named Daniel in 1992.She is also the stepmother to David's son from a previous marriage, Matthew, who is now a budding screenwriter.Didi's son was diagnosed with autism at a young age, and in 2008, she became the official spokesperson for Autism Speaks.She will next be seen on screens in Weekend Warriors an upcoming sports comedy-drama starring Mark Wahlberg.