Gates is co-author, with Chuck Collins, of the book Wealth and Our Commonwealth: Why America Should Tax Accumulated Fortunes, a defense of the policies promoted by the estate tax. He married Mary Maxwell Gates, whom he met at UW, and who died in 1994. They had three children: Kristianne, Bill, and Libby.
Symptoms of heartworm disease may include loss of appetite, lethargy, exercise intolerance, weight loss, fever, dyspnea (difficult, labored breathing, shortness of breath), coughing, weakness, dull dry coat, and hemorrhage. There are no symptoms at all until the disease is advanced.
Some dogs will show symptoms relatively quickly while others may never exhibit symptoms of infection at all. The manifestation of symptoms related to heartworm disease is more directly affected by the severity of the infection and the age and overall health of the dog in question.