I've now read the list of children of Thomas & Betty, having found where my computer had hidden it.
I've also looked at Thomas Whitaker life events in Rochdale on LANOPC.
There were 2 Thomas and Betty couples having children baptised in Rochdale in 1790s.
2 marriages at St. Chad's, Rochdale might have been them:
6th Nov. 1788 Thomas Whitaker & Betty Redfearn
4th Jan. 1795 Thomas Whitaker, widower, this parish; Betty Shepherd, widow, this parish. Both made their mark. Witnesses Thomas and George Fletcher. Married by licence.
Burials of interest at St. Chad's:
*10th Nov. 1793 Betty Whitaker, wife of Thomas; abode Rochdale; occupation tailor
29th Nov. 1812 Betty Whitaker, wife of Thomas; abode Rochdale
There were other Betty Whitaker burials.
This may be burial of one of their children at St. Chad's: 8th Aug. 1792 Mary Whitaker, daughter of Thomas; abode Bank Yard; occupation tailor. (She may have been the Mary baptised in July.)
*10th November was same day as daughter Elizabeth's baptism.