Mrs. Brunton was real, but became a fictional character to me when she rode Nightingale into Fortrose. She died in February 1888, aged 68:
The late Mrs Brunton was interred in Fortrose cemetery on the 7th inst., when a large number of relatives and residents assembled to pay their last respects to the departed. The deceased lady’s illness was a protracted one, borne with Christian resignation and fortitude, and of her it may be truly said her end was peace. Southland Times, Issue 9752, 15 February 1888, Page 3