Need Help with Family History

I need help from the older generation or anyone with knowledge of the House of Detention in Clerkenwell. In the mid to late 80's I visited the prison site under a school to consult on asbestos removal and afterwards mentioned to my father that I had been there. He told me that he had grown up in a pub nearby where he was fostered by the landlady Mary Ann Jessie Cooper. She was born in 1844 and died shortly before her 100th birthday in 1944. Typically I filed the information in memory for later use but then my father died and I have no more information. I am trying to trace my grandmother a Miss L. Andrews who was, I am certain a neice of Mrs Cooper. Mrs Cooper was married to Henry Percy Cooper, son of Michael Cooper and Freeman of the Merchant Taylor's. This alas, is all I know of this branch of my family. If I can trace Miss Andrews I may be able to get further back on my fathers side of my family and am convinced that somewhere in London someone must know something. Please respond if you can help, I've exhausted all other avenues

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