She's sparked outrage and concern from viewers after being excused from three Bush Tucker trials.
But while producers are yet to reveal the nature of Rebecca Adlington's 'mystery' illness, her fiance Harry Need has confirmed that the Olympian has a 'serious medical condition.'
I'm A Celebrity fans are becoming increasingly irate at the swimmer's 'special treatment', which is now rumoured to be due to her asthma, after she was ruled out of ANOTHER trial on Wednesday night's episode.
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But Rebecca's family insist that it is the producers' decision to excuse her from the trials, and have urged them to tell viewers what's actually wrong with her.
Harry wrote on Twitter: ''Becky is a tough cookie, if It wasn't something serious then obviously she would be straight in there eating a cockroach.''
Her aunt, Sonia, told The Mirror: ''We have been sworn to secrecy. Becky wants the public to know why she is being excused. We wish the producers would say the reason.''
She added: ''It's not Becky's choice. She wants to do the challenges - even eating grubs - but she is not allowed to do some of them on doctor's orders.''
While asthma is now thought to be the main reason behind her medical issues, rumours have circuated that it could be to do with her claustrophobia or even because she might be pregnant.
This Morning presenter Phillip Schofield even waded into the debate, voicing what a LOT of viewers seemed to be thinking on Wednesday's show.
He said: ''If you are that claustrophobic then you shouldn't have gone in the first place.
@BarlieChaker22 becky is a tough cookie, if It wasn't something serious then obviously she would be straight in there eating a cockroach �— Harry Needs (@Harryneeds) November 26, 2013
''Whether it's severe enough or whether they are being soft on her out there or whatever. But I'm sticking my flag in that and I'm saying claustrophobia.''
But it seems that claustrophobia was ruled out on Wednesday night as Becky took part in a group trial, involving being trapped in a jungle coach in complete darkness for 90 minutes.
Becky's sister Chloe posted on the swimmer's Twitter page: ''Becky and the other celebrities aren't aware what the trial is each day, it's the doctors who rule out the contestants #imacelebrity.
She added: ''Even we don't know what the medical grounds are. Becky was in good health when she left and definitely isn't pregnant! #imacelebrity.''