Catherine was the daughter of John Barlow MP and his second wife, Anne Skrine.  She married Sir William Hamilton, son of Archibald Hamilton and his wife, Jane Hamilton, on 26 January 1758. In 1764 her husband was appointed ambassador to the Court of Naples. By all accounts it was a happy but childless marriage.
Catherine died at Naples on 25 August 1782.
No Baptismal record for Catherine has yet been found.
Burke as cited by Peerage gives her father as Hugh Barlow  which agrees with Hugh as husband of Anne Skrine as given by History of Parliament online.  However the will of Hugh Barlow makes it clear that by 1761 Hugh had no heirs of his body therefore Hugh as Catherine's father has been discounted.
That Hugh was Catherine's father is further reported in Wikipedia:  " When Catherine's father died in 1763 she inherited his estates in Wales and these provided the Hamiltons with a steady income." The will of Hugh Barlow reads "I do Hereby give and devise all and singular my freehold _____ messuages, collieries, lands tenements and herediments whatsoever and wheresoever whereof I am seized......................unto my wife, Elizabeth Barlow for and during the term of her natural life without impoverishment of waste." After her death the property is to pass to one Hugh Owen.  That doesn't leave much for Catherine and her husband, Sir William Hamilton.
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