This episode, "My Brother's Keeper," was the first time that Tim Daly and his sister Tyne Daly co-starred in a production. They have done this three times: this episode; the 1999 television movie "Execution of Justice (1999)"; and an episode of "Judging Amy."
Mimsy's character is taken from a word in a passage from the Lewis Carroll poem 'Jabberwocky': "All mimsy were the borogoves".
The scene with Webber and the greyhound dog dressed like Sherlock Holmes was stolen directly from A Man's Best Friend (1962) where Bill Bixby shows up with a large dog (a Great Dane, in his case) thus decked out. Both dogs also wear a fedora.