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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Sixteen people have been arrested in connection with an illegal rave in Lincolnshire in which three police officers were injured.
A goalless draw at home to Manchester United condemned Hull to the Championship next season.
A lot of dry weather around over the next few days, but not wall-to-wall sunshine and temperatures average at best