... because I wondered how the show handled the abrupt change in cast. The answer - not that well.
The first scene establishes why George and Dorothy Baxter are missing. It is some weird story about an oil deal George is involved with in...Baghdad??? Wow, how things have changed! And George took his wife along(!!!) but left their son with Hazel because of wanting to keep him in school. So Hazel and Harold are bundled off to the home of George's brother, Steve. Steve is married with one child, I guess to preserve some continuity, but three helpings of mashed potatoes is not the same as three helpings of caviar.
The problem is that this new cast is completely flat. I know I've seen the actor who plays Steve, Ray Fulmer, in other things, but here his character has the personality of a mortician (my apology to morticians everywhere) when compared with Don DeFore's great chemistry with Hazel as George Baxter, a man who was used to being captain of his fate who married a woman and got a mother hen of a maid in the process.
Oddly enough, this new and not improved version of Hazel had good ratings. It only ended because Shirley Booth had health problems that made the busy schedule of shooting a TV episode a week too taxing for her. I'd rather remember Hazel from its great first four seasons.