The Essex Regiment Museum
In the early hours of the morning, staff report hearing a child's laughter; there are also stories of a slamming door being heard.
Update 23/7/21: Dr Mark Curteis, the Assistant Museums Manager (Curatorial and Learning) of the Chelmsford Museum informs me, "There have been no reported "odd" or inexplicable phenomena at The Essex Regiment Museum."
Link: Essex Live
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