Happy Father's Day! We're celebrating dear old Dad with a collection of radio mysteries featuring fathers. First, Ellery Queen and his police inspector father collaborate on a case of smuggling and murder. Larry Dobkin is Ellery in "Number Thirty-One" (originally aired on NBC on September 7, 1947). Next, George Valentine is hired by a convicted killer's son to clear his father's name. Bob Bailey stars in "The Father Who Had Nothing to Say" from Let George Do It (originally aired on Mutual on September 13, 1948). Then, meet private eye Joshua Sharp - known to his kids as The Big Guy. Henry Calvin plays the shamus and doting dad in "The Unheard Voice" (originally aired on NBC on May 7, 1950). And finally, Philip Marlowe hunts for a missing son for an ailing father. Gerald Mohr plays Marlowe in "The Last Wish" (originally aired on CBS on July 19, 1950).