When word arrives that his old friend Mo Jackson has died, Granddad and the boys embark on a trip back home to Chicago for the funeral. During the plane ride, Granddad recounts how, as young fighter pilots during World War II, he and Mo competed head to head with each other as they fought the Nazis. When Huey points out that he doesn't seem to be very sad over his old friend's passing, Granddad notes that Mo was disloyal and did something that could never be forgiven. But once they arrive back in their old neighborhood, Granddad is stunned to discover that, along with what he's being given in the will; Mo has left specific instructions for him to deliver the eulogy as his ashes are placed into Lake Michigan. Meanwhile, Huey is upset to learn that his best friend back in Chicago, Cairo, has ditched him for someone new. On the party boat that's been outfitted for the occasion, Granddad joins Mo's family and friends for the funeral. However, already upset to discover that the Mo's memorial includes a war medal that actually belongs to him, Granddad learns that his old friend was badmouthing him right up until the day he died. So, after accidentally killing the dove that was released with the late man's ashes, Granddad cannot hold his tongue any longer and proceeds to tell everyone how petty, immature and selfish Mo really was. And though Mo's widow takes offense at the harsh words, nearly everyone else at the funeral agrees. As the mourners argue over the late man's legacy, Granddad uses the occasion to tell Aunt Cookie how he never forgave Mo for having stolen away a girl that he thought he might have married someday. But, after Cookie reveals that the girl in question turned out to be more than just a little ugly, Granddad realizes that he has wasted the last fifty years hating Mo. Finally, after Huey discovers that what he had with Cairo can never be reclaimed, Granddad expresses regret for letting his friendship with Mo die, only to learn that all he's been left in the dead man's will is an old jar of peanuts.