You can see George, Donald, & Catherine on the 1900 Census records here:
http://labs.familysearch.org/ There is also a transcription of the 1920 Census there, and they are in Brooklyn both times.
In the 1930 Census, George & Catherine are still in Brooklyn. Catherine is age 73 & a widow. George is age 35, single, dean - law school, and a WWI veteran. Both are listed as immigrating in 1897 and are aliens.
A passenger list for the SS Transylvania from Glasgow to NY, arriving 25 Jul. 1931, has George, age 37, single, a US citizen, US passport #388699, and Catherine, age 76, a widow, a US citizen, US passport #388700. Both were living at 1002 Bergen St. in Brooklyn.
A passenger list for the SS Aquitania from Southampton to NY, arriving 28 Jul. 1933 lists George w. Matheson as single, age 39, a US citizen naturalized by his father's papers, and living at 1002 Bergen St. in Brooklyn.
A passenger list for the SS Monarch of Bermuda from Hamilton, Bermuda to New York 5 Jul. 1934 has Dr. George Matheson, age 40, single, b. 1894, naturalized by father being US citizen, living at Tower's Hill, Brooklyn, NY.
George appears on a passenger list for the SS Kungsholm from NY to NY from 6 Jan. to 25 Jan. 1937. He is age 42, married, and with him is Mrs. G. Matheson, age 25, born Brooklyn, NY on 12/6/1911, and they were living at 25 Clark St., Brooklyn.
The death index at
www.italiangen.org shows a Donald Matheson, age 68, who died 4 May 1923 in Kings Co. (which is Brooklyn). There is also a Catherine Matheson who died at age 75 on 26 Nov. 1932 in Kings Co.
