Robert Kyd, parents William Kyd and Elizabeth Leith, was born on 7 and baptised on 16 December 1841 in Arbroath. Unfortunately none of the other children's baptisms are recorded in the readily available records, and the marriage too seems not to be on record.
I see that the family at Barn Green in 1841 comprises William Kyd, 50, shoemaker; Elisabeth, 50; Margaret, 20; Elisabeth, 15; and Jean 15, plus Alexander Reid and Smith Reid, both 20.
There is a 2-year-old William Kydd in the household of Elizabeth More, 65 and Susan More, 25 in Lord Burn, Arbroath, and a 1-year-old William Kydd in Panmure Street with William Kydd, 25, shoemaker, and Margaret Kydd, 25. Although the age isn't quite right, the latter looks more likely to be the right one.
I have completely failed to find Isabella Finlay in the 1841 census transcription at FreeCEN. I had hoped that this might give a clue as to her origins.