Possibly Mickle and Mickleby ane the same people.
IGI has Margaret Mickle marrying William Gilmor.

1851 Census
Robert Gilmour 25 unm head Schoolmaster b St Anne
Margaret Wid mother 60 b Malew
John 19 Bro unm Shoemaker Appr b St Anne.

The IGI has no Mickleby christenings in Malew.
However there are five Mickle christenings:
Thomas and James both christened on Sept 6 1789, Frances Mickle on July 7 1800, James Mickle May 18 1805, Eliz on Nov 1 1801, all born to James Mickle and Margaret Clague.
Frances married Robert Kermode on June 3 1826 in Santon as Mickleby.