In the episode Mother's Helper there is a blooper that always has bugged me. When Margie is mopping the kitchen floor and Beaver walks in, she is using a sponge mop. Minutes later Wally walks in the back door and tracks in mud, there is now a close up of the muddy footprint and the mop, only in the closeup the mop is not a spongemop, but a string type mophead, obviously the closeup was added later and the director used another mop.

I saw that episode a few days ago. I noticed when Wally comes in he tells Margie where to dump/or get more water from the laundry room. I question Where did she get the existing water. I would have thought June would have told where to go for dumping and getting water, not Wally. At first I thought she got it from the tap. IF so why not dump it there too.
Also the actress could have played Gilbert's sister. The face looks similar.