Other mistake: In this episode, they have a leak in the roof. Yet, the house is a two story house with an attic. So it should not be able to leak into the living room. Also, when Carl and Eddie go up to fix the roof, Eddie falls through the roof and ends up on the living room couch. Again, two story house with attic. Should not happen.
Good Night, Dear Heart - November 9, 1957 - S2-E17
Other mistake: Sam opens Hila's diary to a page. The translated voice-over mentions the 4th of July, America's independence and how she met someone with whom she could fall in love etc... The actual text on the pages mentions only the "Beginning of July" and how "3 bears and a zebra were born in the zoo. "Anton" was there and told her about it. His entire family was there and had a lot of fun." The right-hand page mentions how they had a wonderful day visiting the castle at Chiemsee where they had lunch. (00:21:02)
Other mistake: When Hastings pulls Poirot's slip of paper out of his pocket, he's reading it upside down - as you can see from the close-up, the torn up part should be at the bottom, not at the top. (00:11:40)
Other mistake: In the starting titles, the newspaper clippings state that Doogie sails through high-school in 9 weeks, the article says he is 12 years old. The next clipping says he graduates from Princeton at age 10.