Two-year old Jasmine Westgates's father Bruce said: "She ingested some of it too which could have had harmful consequences. There are potentially life-ruining diseases linked with coming into contact with animal faeces.
"I have lodged a complaint with officials at the garden centre. If a play area is open to members of the public then you have to look after it better than that."
Whitminster-based Highfield Garden World managing director Joan Greenway said: "We would like to apologise to the Westgates for what happened.
"We clean and inspect the sandpit every day during the week, although not on weekends.
"We are surrounded by countryside and a fox must have come during the night. We might well have to close the sandpit because of this, which is a shame because youngsters will miss it. But we can't let this kind of thing happen again."
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