The ex EastEnders actress, 27, shared a make-up free selfie on Instagram and revealed she's been feeling "unwell".
The mum-of-two captioned the pic, posted on Sunday (05.01.20) afternoon: "Okay... let's be real for a sec, yeah? I am unwell, the cold has finally hit me.
"I realised, I spent a month in front of you guys with zero make-up on and bites all over my face, crying like a baby... but at least I was open and real with you guys.
"Then I come back and post loads of glam pictures. Don't get me wrong, I love a glam moment or two! If I am feeling myself I shall post a picture about it (it's a rare occasion when you have kids!)
"But a lot of the time I look like this... plane Jane! Terrible bags because I'm so tired and full of cold! You lot can be so kind to me and then so mean to yourselves. Be nice to yourselves! We all have rough days, lovers!"
Jacqueline's fans rushed to comment on the pic, with one saying: "Rest yourself, beautiful soul xx."
I'm so tired and full of cold!
Another wrote: "Get well soon @jacjossa xx."
A third put: "Feel better soon xx."
Someone else joked: "In bed [for] two days with the flu and I only wish I looked like you do in this photo, instead of a 40-year-old corpse who needs a shower."
A fifth said: "Hope you feel better after a good night's sleep."
At the end of her post, Jacqueline - who shares Ella, four, and Mia, one, with husband Dan Osborne - teased that she has something exciting in the pipeline.
She wrote: "In other news, I have a super fun announcement tomorrow so I need to pull my act together and take all the medicine I'm allowed to! I need to look cute! So much love."
Jac's illness comes ahead of a trip to Malibu with her friends.
The Sun reported that the star is due to jet off for a girls' holiday in the Californian beach destination, home of stars including Jennifer Aniston, Lady Gaga and former Albert Square favourite Patsy Palmer.
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