A 14 month-old girl from the Sandringham Drive area of Sutton-On-Sea was taken to hospital in Grimsby, suffering from a suspected brain injury on July 28.
She was transferred to Sheffield Children's Hospital where she died from her injuries.
A 30 year-old local man has been arrested on suspicion of murder and is currently being interviewed at Skegness Police Station, Lincolnshire Police said.
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The son of the Yorkshire Ripper's first victim has responded to a letter sent to ITV Calendar by the serial killer.
The former England cricketer reportedly suggested he would have a better chance of being knighted if he "blacked up".
The two-page letter addresses allegations that Sutcliffe attacked men before murdering 13 women