Stacey Solomon shocked fans as she worked out with her rarely-seen sister on Tuesday.
Loose Women star Stacey, 33, introduced Sam to her Instagram followers ahead of their exercise routine in her garage.
Her stunning sibling was a little camera-shy and ran away from view as soon as she got the opportunity to, though.
Stacey often posts snaps of her older sister Jemma, 35, and it is also known that she has two other siblings, Matthew and a half-brother Josh, 18.
But this marks the first time fans have seen Sam, who is a personal trainer at Barry's Bootcamp.
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The former singer explained, "My sister's come round to give me a gym session. This is Sam, everyone. Sam is very camera shy. Not real life shy, just camera shy.
"But you all were like, "Who the hell is this mystery sister?" So here she is. We're about to have a little gym class together and this is the gym reality.
"We also run a creche alongside it with our two daughters, Poppy and Rose, because they're both the same age. So it works out perfect.
"But yeah, this is my beautiful sister. Love you."
Stacey has previously said, " She's actually my step-sister but I would never call her that because we grew up together, so she's my sister."
Her half-sibling Josh shares her dad David, who divorced Stacey's mum Fiona and went on to welcome him with a new partner.
The Sort Your Life Out star was 15 when her baby brother was born, two years before having her own first child, Zachary, 15.
And while in her 2019 autobiography, Stacey admitted she was "very close" with her little sibling, she rarely shares photos with him.
Josh, who describes himself as a music producer online and has a verified Spotify page, also rarely refers to his famous sister.
In their last photo together, Stacey joked she and Josh were both suffering from pimples as she posted a selfie of them together.
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"I love my little brother so much that I appear to be experiencing sympathy puberty. Or at least that’s what we’ve called it," she joked.
"Had the best laugh with my little bro tonight talking about all things hormone induced and I’m grateful to my spots for making that happen. Love you, Josh!”
Stacey's younger brother Matthew stays completely out of the limelight and is rarely mentioned by the star.
While little is known about his personal life, the mother-of-five did reveal that he was getting engaged back in 2019.
Meanwhile, Stacey regularly poses with her sister Jemma, who also has her own Instagram account about being a mum-of-three.
