Four-year-old Jessica Knight carries a small purse filled with sponge from her carpet. The purse is a safety measure imposed by the British girl’s mother, Kelly, to ensure she doesn’t overeat the material and cause harm to her body, metro.co.uk reported.

Jessica, of March, Cambridgeshire, has a rare disease called Pica, which causes a pathological craving for nonnutritive items, such as clay, coal, paper, or food ingredients, like flour or raw potatoes, according to the Psychiatric Times. In Jessica’s case, it’s the underlay of carpet and household furniture. The disease’s prevalence is unknown, but it’s most common among pregnant women and children.

“I was really shocked when I realized just how much she was eating,” Kelly Knight, 36, told metro.co.uk. “If you lift up the carpet in her room, now you can see there is no underlay left.”

Kelly Knight said nothing has deterred the little girl from wanting to eat inedible substances. When she warned Jessica her habit could cause her to become sick, Jessica began eating the items in secret. Jessica’s father, Chris Knight, 40, and Kelly do not know what to do, as their doctor won’t intervene until the little girl turns 6, metro.co.uk reported.

“We are at our wits’ end,” Kelly Knight said.

Jessica doesn’t like foods with sauces, so her mother feeds her plain food including cheese, sausage, bread, and  fish sticks without bread crumbs.

According to metro.co.uk, the family will receive test results that indicate whether Jessica has autism, a condition that has been linked to pica. The little girl underwent the test after doctors saw she had an extremely high IQ.

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