Looks as though you could be searching for John Nisbet b 1820 to George and Martha Hart Nisbet.
Andrew Nisbet and his wife margaret Stewart had Andrew 10 Jan 1749 in Edingburg. Francis8,April 1751 and John 29 Sept 1753 Both in Edingburg.
Andrew m 10 May 1753 at Cannongate Parish to Catherine Guils (Kathron Goold) b 27 April 1753 at Tranent Haddington East Lothian Scotland. She was baptised29 April 1753 the daughter of George Guild nad Janetand died in PEI19 March 1846 Andrew died Ca 1790 in Scotland Janet b 5 June 1774 Rdinburg George b 29 March 1776 d in PEI bef 1861 Andrew b May 8 1778 Margaret b 216 Sept 1780 Margaret b 16 Sept 1780 Alexander b 30 Oct 1783 Swan b 31 May 1787
George m in Paisley Renfrew Scotland to Martha Hart and had Andrew 26 Sept 1804, William b 2 Jan 1806, Martha b 1811, George b 1814, Catherine b 1817, John b 1820, and Thomas b 1823.
My sources are Norma Falconer on line , PEI Master Genealogy Index available at NEHGS in Boston, Personal records of Sarah Nisbet Spencer and of Margaret Kennedy of PEI. IGI and Parish records of Scotland.
Hope this helps. What is your connection to John? Good Luck Hattie