Hi Sue,

Hard to believe Thomas Mylvorrey had only one sibling! The Morrisons I've been following have been prolific, often 9 children, hardly less than 4, and mostly boys.
I thought it may help someone searching on your end to find out what happened to a Morrison ancestor that traveled far afield, so I put together a descent of sorts.
I'm related through:
John Morrison bp 24 May 1789 Maughold – bur 15 Jul 1877 Maughold
married 3 Dec 1814 (both of Maughold Parish) to Margaret Fargher bp 1 Mar 1795 Maughold – bur abt 1870 Maughold. Their children: (all born Maughold)
Margaret bp 14 Aug 1815; John bp 17 Aug 1817 (d. abt 1896 Ontario, Canada); Thomas bp 21 Nov 1819; Esther bp 24 Nov 1822 (bur 19 Dec 1896 Douglas); Ann bp 20 Nov 1825; William bp 29 Apr 1828; Robert Patrick bp 7 Nov 1831; James Henry bp 26 Apr 1835.

through their son:
John Morrison
bp 17 Aug 1817 Maughold - d. abt 1896 Ontario, Canada
marr: 25 July 1840 New York, USA (Registered in Andreas Parish Registry Isle of Man) and
Mary Ann Teare, bp 30 May 1819 Jurby - d. 1868 Ontario, Canada

Immigrated to USA 1826, they returned to Isle of Man about 1841, sailed back to US 1851, moved to Canada about 1861, where they settled. Their Children:
John J., b. 23 Dec 1841 New York, USA, - bp 3 Nov 1843 Andreas, IOM - d. 1911 New Jersey, USA,
William, bp 3 Nov 1843 Andreas, IOM, d. 1895 NJ, USA, Mary Ann, bp 23 Nov 1845 Andreas, IOM, d. USA,
Thomas, bp 6 Feb 1848 Andreas, IOM, d. 1903 NJ USA, Robert, bp 18 May 1850 Andreas, IOM, d. 1852 NY USA,
Eliza Jane, b. 1853 NY, d. 1875 Ontario, Canada, James, b. 30 Jun 1859 NY USA, d. 2 Dec 1920 Oregon, USA,
George, b. abt 1862 NY USA, d. 27 Dec 1925 Michigan, USA (no marriage),
Sidney, b. Aug 1865 Ontario, Canada, d. Apr 1951 Ontario, Canada

their son, my ggGrandfather:
William Morrison, bp 3 Nov 1843 Andreas, IOM, d. 25 April 1895 Newark, New Jersey, USA

Thanks again, Sue

Blessings,
Brenda