Not the son of Hugh Fraser, 5th of Lovat & Janet Dunbar
Hugh Fraser, 1st Lord Lovat at Wikipedia
According to James Balfour Paul's 1908 volume 5 of The Scots Peerage, Hugh Fraser, 1st Lord Lovat was the son of Thomas Fraser of Lovat but it is not known who Thomas's wife was. Hugh succeeded his father before May 1455 and as a minor was put under the care of Archibald Douglas, Earl of Moray (d. 1455).[1] …
So http://thepeerage.com/p39239.htm#i392382 which is Burke’s based had Hugh Fraser, 1st Lord Fraser of Lovat parents as Hugh & Janet.
But The Scots Peerage, which is a more modern, accurate and cited source, doesn’t show this Hugh Fraser, 8th of Lovat at all, and expresses skepticism at the existence of Janet Dunbar.
The source, MacKenzie, Alexander. "History of the Frasers of Lovat, with Genealogies of the Principal Families of the Name to which is Added Those of Dunballoch and Phopachy", Inverness: A & W Mackenzie,1896, Archive.org, p. 57, https://archive.org/details/historyoffrasers00mackuoft/page/57/mode... has a much bigger family, doesn’t seem to have Thomas, and doesn’t cite their work. I’m not sure how reliable this source is.
The most recent source from Clan Fraser follows The Scots Peerage with an addition of two sons for Hugh, 1st Lord Lovat, rather than only one in TSP.
I guess the next step is to prune extra children.
Children of Hugh Fraser, 1st Lord Fraser of Lovat not supported by the modern Clan Fraser of Lovat have been detached and attached to N.N. Fraser Agnes Fraser; Anne Fraser; John Fraser; Janet Fraser; Alexander Fraser, 1st of Farraline