To many boomers, Jaclyn Smith was the ultimate 70s beauty, with her sculpted cheekbones, gorgeous smile and glossy chestnut waves.

And while her other Charlie’s Angels co-stars, such as Farah Fawcett and Cheryl Ladd, came and left, Smith, now 76, outlasted them all. She was the only one to remain on the smash hit television series which defined the 70s for all five years, from 1976 to 1981, playing Kelly Garrett (unofficially, the Classy One).

The Charlie’s Angel veteran has now proved that her age-defying beauty is still very much intact by sharing a rare family photo on her Instagram account this week, Wednesday, December 16.

In the new post, the brunette bombshell poses with her only son, Gaston Richmond, 39, from her home in Beverly Hills, California, and fans have been quick to point out that they could well be “brother and sister”, instead of mother and child.

The loving caption reads, “My son-shine.”

Smith, who has added youthful blonde highlights these days to her trademark long and thick dark locks, is wearing a petrol blue long-sleeved satin blouse and flatteringly understated make-up, as she embraces her son Gaston, whom she shares with third husband, Anthony B Richmond, 79.

With his salt-and-pepper beard and greying hair, Smith, now a clothing designer, could easily pass as the younger of the two.

Wrote one of Smith’s many Instagram followers: “You look like brother and sister (red heart emoji).”

Although it has been decades since the photogenic star was a 70s pin-up, she has famously held onto her looks by exercising regularly and practising yoga, and judging by her Instagram account, is also a devotee of healthy green smoothies, made with kale, cucumber and celery.

Smith also delighted her 160,000 followers on December 7 when she posted a series of enchanting images of her young granddaughter, Bea, dancing around her exquisite Christmas tree on a black and white marble floor in Smith’s lavish Hollywood home.

And while it’s also been half a lifetime since her Charlie’s Angels’ heyday, the era is clearly still very close to Smith’s heart. An Instagram post from October 17 shows her blowing out the candles on a surprise 76th birthday cake from her husband: a giant chocolate gateau, decorated with three vintage postcards from the cult hit show.

For the 45th anniversary year of Charlie’s Angels, Smith has also posted some wonderful throwback photos of she and her fellow Angels alum, Cheryl Ladd and Kate Smith, such as these two nostalgic images.

Smith has said that she remains closest to Ladd, who starred as Kris Munroe for 87 episodes. She has also expressed sadness at the death of former angel, Farrah Fawcett, who played Jill Munroe. Fawcett died in 2009 after losing her long fight with cancer.