(Well, approximately)
This is a photo of CZJ winning a Butlin’s talent contest in 1979. (Butlin’s is a holiday resort/camp in Minehead.) The picture was supplied by the camp, not by Zeta. The photo is completely consistent with her stated birth year of 1969. As always with stars, she may have fudged a year, but she’s clearly not much older than ten in that picture. Here is a pic of her accepting her trophy, and it shows that she is clearly pre-adolescent.
(About a decade ago, there was a rumor going around that she was about ten years older than she claimed.)