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She's likened herself to the Antarctic creatures while tweeting about her current pregnancy.
She told her 3 million+ followers on Twitter: "I feel like a penguin, not the chocolate covered biscuity kind, but an actual penguin that waddles. Now can't stop thinking about chocolatey penguins, doh!"
Allen had previously tweeted on Sunday that: "I can't see my toes and I'm not bendy anymore."
She married builder Sam Cooper at a ceremony in June; the newlyweds announcing her pregnancy at the same time following a tragic miscarriage last November.
Lily also recently congratulated Amanda Holden on the news that the Britain's Got Talent judge is expecting, also after sadly suffering a miscarriage last time around.