Thanks, I hadn't got the Mary burial in 1784. and that John's father was Walter
I am wondering whether the Mary baptised in 1776 was actually Walter's daughter and there was an error in transcription or the original baptism record.
I have Walter Sibley and Mary Cox marrying in Holdenhurst on 24 Nov 1766.
Children of Walter (no mother mentioned):
John bapt 21 Dec 1766, buried 3 Dec 1775
Betty (my direct ancestor) bapt 11 Dec 1768,
Ann bapt 18 Mar 1770,
Thomas bapt 31 Oct 1773,
Sarah bapt 8 Mar 1778
Mary would fit nicely between Thomas and Sarah.
I have a burial for Walter Sibley on 23 Aug 1786 in Christchurch.
Also a marriage for a Mary Sibley in Christchurch by licence to a John Swetman of Wimborne on 14 Jan 1789. Although it doesn't say she's a widow it could be Walter's widow remarrying.
The witnesses were Abel Thomas (x) and John Kent.
The only Abel Thomas I can find in right place and time frame is father of Mary Thomas who married John Derham, who was the brother of the James Derham who married Betty Sibley (daughter of Walter and Mary)