Killamarsh murder victim, 11, had been raising money for cancer charity the day before she died

But the next day, devastated friends and family were mourning her death.

Neighbours have told how 11-year-old Lacey Bennett had been seen out and about raising money for cancer research – and had planned to pass the money on to the Teenage Cancer Trust, which had been raising money in Killamarsh recently.

She and her friend, thought to be Connie Gent, had set up a stall in the nearby park and were selling items such as biscuits, cakes, sweets and lollipops.

One neighbour described them having set up a stall at the end of their street. They said they understood the girls had planned to return the next day to raise some more money for charity.

That never happened. Lacey and her best friend Connie, also 11, were found dead at Lacey’s home on Chandos Crescent on Sunday morning along with Lacey’s mum Terri Harris, aged 25, and older brother John Paul, aged 13.

Friends have been paying tribute, leaving flowers at the end of the street, while police continued their investigations on the site.

Flowers have been left next to the street sign, at the edge of the police cordon, since police revealed that four people had died and a murder investigation was underway, yesterday morning.

Police had been on the street, which they sealed off with blue police tape, since early on Sunday morning.

One neighbour said what happened was horrendous. "We used to see the kids playing in the field near their house at the weekend,” she said.

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Tributes paid to mum Terri Harris after man is arrested on suspicion of murdering her and three children in Killamarsh

Dad weeps as he leaves flowers for his children found dead in Killamarsh suspected murder

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