Goose I have just reread your original post.
Excuse me? This woman bought a house, presumably with a full survey and report, and knowledge of what was in the deeds. Now, two years later, she decides that a) she does not like where the boundary is set, although it has been there for 100 years, and b) that she does not like the fence which you built, at your expense, on your land, and wants it replaced!
Has she offered to pay for this replacement, or does she expect you to pay for it yourself?
Has she been eyeing up your choice of plants, with a view to getting you to change them for ones which match her planting scheme?
Should you be repainting your front door to suit her? Are your curtains up to scratch?
One of my neighbours came home from work one day to find that the people in the semi next door has erected a solid 6ft wooden fence from their front gate to their front door. The doors are about 3 ft from one another, so are the gates. So she painted her side lilac and planted climbers up it.
Your daughter's neighbour has many options if she does not like what she sees.