It pierced little Siann Parkinson’s thigh as she rolled down a grassy slope in her local park.
Mum Annabel, 25, heard her scream and rushed the blood-splattered child to hospital — where Siann was given a Hepatitis B injection and had blood tests.
She needs more tests over the next two months before doctors can tell whether Siann has contracted the potentially-fatal disease.
Distraught hairdresser Annabel said: “It will feel like an eternity.
“The risk of infection is small but it’s like there’s a big, black cloud hanging over us.”
The incident happened a King’s Park in Bournemouth, Dorset.
Annabel added: “It’s somewhere drunks and drug addicts congregate.
“Something should be done to ensure that families are safe.