The former model, who presented Celebrity Love Island back in 2005, made the dig on her Heart Radio show, also bringing up Caroline’s rumoured romance with her ex-boyfriend Danny Cipriani.
Kelly said: “I can’t believe she’s doing Love Island and dating Danny Cipriani.
“I was like, ‘Is she just following my life or something?’. Hang on, I was the first host of Love Island, then I dated Danny. It’s like, what’s next?
“Is she going to come and start hosting this show next?”
She continued: “I don’t know if she’s still dating him. But when I look at stuff like that I’m like, ‘This is just weird. It’s just weird’.”
Kelly’s stint as the co-host of the original Love Island came to an end when she was dropped after just one season.
Fearne Cotton was then drafted in to present the second run alongside Patrick Kielty in 2006.
Caroline has been at the helm of the rebooted ITV2 version since its inception in 2015, where ratings have increased year-on-year.
In recent months, the former Xtra Factor host has been linked to rugby player Danny, who Kelly dated on-and-off between 2010 and 2013.
However, it was recently claimed Caroline had called off their short-lived romance having first been spotted together in April.