MARINE PARK - Police say that a man stabbed in Gerritsen Beach is the brother of a man whose beaten body washed up on the shore this morning. Police say they are questioning a suspect, Sam Edison, in both the stabbing and the fatal beating cases. A man who claims he is Edison's brother-in-law says police came to his home on Fillmore Avenue before taking him to a local precinct. Police say the stabbing happened near a Laundromat on Gerritsen Avenue, and that the body that washed up in Plumb Channel has been identified as Timothy Murray. The stabbing victim is in stable condition at Kings County Hospital.