There are 2 sons I found at ancestry.com for Lorraine Sorenson

Minnesota Birth Index, 1935-2002
Name: Robert Warren Grant
Mother: Lorraine Elsie Sorenson
Father: Clyde Edward Grant
Birth: date - Hennepin, Minnesota

Minnesota Birth Index, 1935-2002
Name: Thomas John Grant
Mother: Lorraine Elsie Sorenson
Father: Clyde Edward Grant
Birth: date - Hennepin, Minnesota

Their son Robert W. Grant also seems to live in Owatonna Minnesota. Click here to get his address

http://www.411.com/name/Robert-W-Grant/Owatonna-MN/3e4r4xj