Looking for a John Donaldson who married Sarah Clendennen and lived in West Deer Township, Allegheny Co., Pa and his brother Robert Donaldson who married Sarah's sister Isabel Clendennen. Robert and Isabel lived in Pittsburg, where it is said he was one of the surveyors of the city. They had five children. They are listed in a deed from W. Clendennen of West Deer to his sisters property of their father,James, dated Sept 14, 1849. Robert is found living in Pittsburg in the 1850 census. Does anyone have these Donaldson's? Lori