A spokeswoman said: "Police believe this has been a targeted, domestic-related incident."
The scene was heavily guarded by police today and a white forensics tent had been set up in the front yard of the brick-built terrace house.
One woman in a nearby property, who declined to be named, said: "All I saw were lots of blue lights and this morning they said someone had been murdered - a lass, I think.
"It's a good estate - you don't expect this."
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The child died on her injuries and another 14-year-old girl was injured after the buggy they were travelling in was involved in a car crash.
Cloud thickening from the west throughout the day. Rain in northwest later.
The Songs of Praise presenter has voluntarily agreed not to appear on BBC whilst an investigation takes place.