Read your message, and alto I am not aware of the whole story, I am guessing you are looking for a Rousseau who came from Canada and changed his name to Brooks. Right? If this is the case, try the state of Vermnt Rousseau/Brooks web sites. Because my maiden name was Rousseau and my husbands family contains Brooks, I read all the sites. Seems a Rousseau came to VT and changed his name to Brooks. You might find your missing link there.
E Rousseau Godfrey