Lucy Has Her Eyes Examined - S3-E10
Other mistake: When the eye doctor has Lucy repeat the same letters on the eye chart that she claims Ricky got all wrong, she repeats the same letters out loud, then moves closer to the eye chart and repeats the same letters out loud, then pauses in error when she read them all off correctly: P E C F D.
Other mistake: When Ricky puts the baby in the crib and begins telling him the bedtime story, in the closeups Little Ricky's sitting up beside the crib rails (at Ricky's side of the room), but in all the wideshots when the camera pulls back to show Ricky's lively storytelling, we can see that Little Ricky is not where he should be.
Other mistake: When Ricky and Fred hold up the newspapers with the big holes in the back page, we see the front page with the headline "Bond Issue Defeated", and it should look familiar since it's the same front page that was used in the episode "Ricky's Old Girlfriend", with the article about Carlotta Romero. (00:18:15)
Chosen answer: It's not known. She may have moved it to the spare room or it may be in a corner just off camera. There could be any number of reasons, though it probably took up too much room on the studio set, and it was removed, making it easier for the actors to move around.
raywest ★