Michael was born about 1735.
It's unclear where his name came from. The birth year is a very rough estimate based on his son William's birth in 1765. Whitten-1 18:59, 22 April 2017 (EDT)
The following is the Freepages site at Rootsweb, and is put here to aid in finding more information. 
3/5/2021 - At least there was a William Legge in Nova Scotia in the right time frame: Name: William Legg, Residence Year: 1792, Residence Place: Oakland, Lunenburg, Nova Scotia, Canada, Record Type: Poll Tax Roll, Source Citation: Nova Scotia Archives; Halifax, Nova Scotia, Canada; Census, Assessment and Poll Tax Records 1767-1827. Source Information: Ancestry.com. Nova Scotia, Canada, Census, Assessment and Poll Tax Records, 1770-1795, 1827, 1838 [database on-line]. Lehi, UT, USA: Ancestry.com Operations, Inc., 2013. Original data: Halifax Real Estate Valuation, 1775. Commissioner of Public Records collection. Series: City of Halifax, 1749–1869. RG 1, vol. 411. Nova Scotia Archives, Halifax, Nova Scotia, Canada. Fetterly-28 03:52, 6 March 2021 (UTC)
3/5/2021 - The Familysearch.org link in this profile points incorrectly to Olivia Minnie Legge, born 26 Apr 1846 at Scot's Bay, parents: Michael Legge and Ann Elizabeth Lautz. The next column lists date of marriage (of parents) as 1855, the informant being Mrs. A. E. Legge of Scot's Bay. There is also a Legge who married a Russell. But all these marriages occurred around 1850, far too late for this couple. Fetterly-28 03:44, 6 March 2021 (UTC) 1/14/2022: This has been corrected, and points to the 28 Jan 1908 marriage of Michael Legge to Ann Eliza Lantz in Nova Scotia, Canada. Fetterly-28 02:35, 17 January 2022 (UTC)
He (Michael) is sometimes said to have died in the West Indies, but his burial gives his address as Skinners Row and the probate record as Roscawes. 2. Michael Legge b. 1736 at Rodeen, Tipperary d. After 1784, when he writes a letter to William Legge, Earl of Dartmouth.
1/14/2022: More concerning the Michael Legge from Ireland: "A Gent, of Rodeen, Co Tipperary. A list of Freeholders in Co Tipperary for 1775-6 lists a Michael Legge of Leggesborough & Garvane [Garrane?] and a John Legge of Clonmel, Tipperary. Michael Legge married on the 24th May 1759 at the Church of Ireland, Newport, Co Tipperary to Anne Young. Anne was born in 1742 at Brookfield, Limerick, the daughter of Simon Young [born about 1714 & died 16 Jan 1776 in Limerick & was buried at Rathkeale Graveyard, Co Limerick] and Anna Maria Ewer [daughter of William Ewer of Clonsingle, Co Tipperary & Mary Philips of Dublin. She died in 1781].
A gravestone at Rathkeale is inscribed " Mrs Anne Flanedy ered ys stone In memry of her father Simon Young who depd ys life Jan 16th 1776 aged 62 years & her son Edmund Flanedy who died Novr 8th 1799 aged 22 years." This has been suggested as proof that Michael Legge died before 1777 and his widow remarried, but it seems that there are at least two Anne Youngs, daughter of Simon Youngs! (ALSO SEE: * Marriage: "Ireland Diocesan And Prerogative Marriage Licence Bonds Indexes 1623-1866"
FindMyPast Image - FindMyPast Transcription (accessed 16 January 2022)
Michael Legge marriage to Ann Young in Ireland.) Fetterly-28 05:09, 17 January 2022 (UTC)
Michael and Anne Legge had several children, although so far I only know the name of two. His letter to the Earl of Dartmouth refers to an Affidavit listing the names and dates of birth of his children, but so far I cannot locate this. The letter does refer to "my younger children" and two daughters who married without consent and in 1784 are still under 21. The name of one daughter is known because her husband also wrote to the Earl." Fetterly-28 02:12, 17 January 2022 (UTC)
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