Millie Mackintosh's 18-month-old daughter has hand, foot and mouth disease.

Millie Mackintosh and Sienna (c) Instagram

Millie Mackintosh and Sienna (c) Instagram

The 32-year-old star has taken to Instagram to reveal that her daughter Sienna has been diagnosed with hand, foot and mouth disease after being rushed to hospital.

Millie - who is currently pregnant with her second child with husband Hugo Taylor - wrote on the photo-sharing platform: "It’s been a rough few days in the Taylor household, Sienna has really not been herself. I put it down to having a cold and possibly teething as she kept crying and pointing at her mouth, by the end of the week she was refusing to eat or drink anything, even the sight of her milk bottle would make her scream so I knew it was something more.

"We took her to A&E and they found ulcers on her tongue and the roof of her mouth, they diagnosed her with Hand, Foot and Mouth. Her throat is very sore, apparently it’s like tonsillitis but worse. I felt so bad for not realising, but she doesn’t have the telling rash around her mouth or on her hands and feet - but apparently that can come later. (sic)"

Millie - who posted a photo of herself and her daughter on Instagram - admitted to being heartbroken about Sienna's health problems.

She wrote: "We have been giving her regular pain relief and using a numbing throat spray which seems to be helping a little, she is sleeping more than normal but when she is awake she is crying non stop, which breaks my heart. It’s so hard to see your child unwell and I can’t explain to her that it will be ok.

"She really hasn’t eaten much in the last few days just a bite of her favourite snacks here and there. Thank you for all your suggestions of soothing cold foods after I posted on stories, most things we have offered are angrily refused and thrown across the room but we will persevere! We are still having to administer water with a syringe through out the day but at least I know she is getting some fluids.

"Rules and routine have mainly gone out the window with lots of Peppa Pig and cocomelon! Fingers crossed she turns a corner today and starts feeling better. Sending lots of love to all the parents out there with a sick child, I keep saying to myself this too shall pass [heart emoji] (sic)"