The Coronation Street star enjoyed an evening out with her sister Bernadette at the LGBT Awards 2018 on Friday.
Ahead of the evening out, Catherine treated her 363,000 Instagram followers to a rare capture of the duo.
In the snap, the actress could be seen donning a hot pink Outline suit, which she teamed with a tight-fitting white top.
Meanwhile, the star’s sister sported an all-black ensemble, as she dressed in a black suit and matching shirt.
But while the pair opted for similar outfits, some fans were convinced that Catherine’s sister had more resemblance to a different star.
After seeing the snap, one penned: “I thought that was Sporty Spice!”
“Wow the other lady is the double of @melaniecmusic,” commented another admirer.
A third follower revealed: “I thought that was Mel C.”
The supposed resemblance with the Spice Girl is thought to due to her cropped pixie hair cut.
And, when you compare the photo with a throwback snap of the pop star back in 1999, fans could be forgiven for the mistake.
Catherine Tyldesley Instagram: The star shared a snap ahead of the LGBT Awards last week
Meanwhile, other fans couldn’t help but gush over the duo, and rushed to shower them both in compliments.
“Looking AMAZING guys,” wrote one, while another penned: “Looking amazing ladies! Rocking the trousers suits.”
One very impressed fan told the duo: “That look is powerful.”
“Great make-up and outfits,” added a fourth.
Catherine Tyldesley Instagram: Spice Girls star Mel C sported a pixie cut back in 2000
Explaining that she was doing a HIIT workout, the star revealed that her hectic schedule had meant she had been forced to train in a rather unusual setting.
Talking to fans in the clip, Catherine panned the camera as she announced she would be working out in character Gail Platt’s camera.
“So scheduling has gone breast upwards so I’m doing my HIIT training in Gail Platt’s garden,” she divulged.
Clearly very happy about her new work out space, she exclaimed: “How cool is that.”
Coronation Street continues tonight at 7.30pm on ITV.