The two pop stars were seen together again on the hit ITV reality show earlier this year, along with their groups 911 and Honeyz.
However, we have now discovered that their friendship has in fact been going strong for the last ten years.
Lee posted a fun throwback picture of himself and Célena in their co-ordinating panto costumes on Twitter yesterday (18 December).
He wrote: "Wow!!! @CelenaHoneyz & I in panto in 2003!! I was Peter Pan & she was Tiger Lilly! We have been friends ever since:)"
In the snap, Lee - who was previously married to B*Witched star Lindsay Armaou - can be seen in a fetching white and gold outfit, complete with white headband and that signature spiky hair from his 911 days.
Meanwhile, Célena looks pretty in matching colours, a gold encrusted headband and feathers on her back.
The Honeyz songstress swiftly commented on the amusing picture, saying: "omg!!!!!!! I feel so old!!!!! Look at u cutie xxxx"
Well, we actually think they both look pretty cute!
Earlier this month, Célena admitted that she and bandmates Mariama Goodman and Heavenli Roberts didn't know if they would have any fans left before going on The Big Reunion.
But the trio were soon proved wrong, as they and the rest of the 90s groups on the popular show enjoyed a hectic past few months performing across the country on a sold-out UK mega-tour!
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