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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Detectives are continuing to appeal for information following a ram-raid at a jewellers in Leeds city centre.
Lorna Fillingham started a petition after realising how few places had the full size changing beds she needs for her daughter Emily-May.
Drier and brighter from Tuesday with good spells of sunshine. Turning increasingly colder with widespread frost overnight