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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Josh Warrington will fight for a world title after a 10th round stoppage of Denmark's Dennis Ceylan at the Leeds Arena last night.
The remaining two anti-fracking protestors who climbed a rig at a live well site in Kirby Misperton, North Yorkshire, have been removed.
The incident happened on the A1133 at Laughterton on Friday evening.