http://thepeerage.com/p22837.htm#i228364 Margaret Barton was the daughter of John Barton.1 She married Sir Ralph Assheton, son of Sir John de Assheton and Margaret Byron, circa 1439.1 She died after 1480.1
Middletonia local history.
website http://www.middletonia.co.uk/localhistory/lordsofthemanor.html "Middleton passed to Maud's son John de Barton in the 1360's whos heir was his son Richard born in 1386. Richard's son John died leaving daughter and heir Margery who in 1438 was contracted to marry Ralph Assheton, son of John Assheton of Ashton Under Lyne. Ralph Assheton began the 327 year tenure over the estate of Middleton by the more familiar Assheton family . . ."