John GARNER and his wife had 8 children in Burbage between 1778 and 1792. Only the last four gave a mother's name which was Elizabeth. With christenings initially being every 18 months - 2 years it is unlikely that there were two mothers.
There are two local marriage records for a John GARNER and an Elizabeth:
1. John GARNER and Elizabeth BATCHELOR in Leicester was on 1 May 1776 at St Margarets. This ties in nicely with the christening of their first child, John, but not the precise location. The wedding record states that John GARNER was resident in Lathbury, Buckinghamshire, for the past 4 weeks, but given the number of GARNERs in Leicestershire it's likely that this was a temporary residence. An Elizabeth BATCHELOR was baptised by John and Ann BATCHELOR in Brownsover, Warwickshire (12 miles from Burbage) on 17 Apr 1750. The next nearest baptism found was 80 miles away. Ultimately there is no connection to Burbage though.
2. John GARNER, a farmer aged 30, and Elizabeth ADCOCK, aged 27, both of Burbage. The only record is their marriage bond dated 15 Oct 1777 which John signed. In December 1777 a new curate in Burbage noted that his predecessor had refused to record several marriages, perhaps explaining why this marriage is missing in the Burbage register.
On balance Elizabeth ADCOCK looks more likely on the above evidence, but if their eldest son was John GARNER c1778 then why could John not sign his name when he enlisted in 1797 or when he married in 1802, and why would he become a framework knitter instead of working his father's farm in the expectation of one day inheriting it?
Elizabeth was baptized in Burbage by George ADCOCK on 20 Aug 1750. George was the name given to John and Elizabeth GARNER's 8th child.
An Elizabeth GARNER of 'Burback' (an alternative name for Burbage), aged 77, was buried in Burbage on 2 Dec 1827, the year after the death of John GARNER, 85, was buried there. This Elizabeth GARNER would have been born in about 1750 which matches the baptismal records of both Elizabeth BATCHELOR and Elizabeth ADCOCK.
Another marriage of a John GARNER to an Elizabeth BLYTHE was on 24 April 1783. This was less that 7 months prior to the christening of Robert GARNER, John's 5th child, and who was the first of John's children with Elizabeth given as the mother. So it is feasible that there were two mothers: Mother A who had four children and died in Jan 1782, then Elizabeth who must have been wooed, married in 3 months and given birth less than 7 months later. Unlikely.