Anyone ever notice Eddie appeared in only a few episodes during the second season? I think he might have been in a few early episodes, then he disappeared for the rest of the season.

That's right! He was in a lot of episodes in season 1 then almost didn't reappear until season 3. Seemed Wally didn't have a lot of friends in Season 2. I'll check out how many.

Eddie was in 11 episodes in Season 1, 5 episodes in Season 2 and 11 in Season 3. He is often mentioned by Wally in episodes but we never see him. In Wally's Haircomb Eddie supposedly had everyone comb their hair like that but we only see the Lump.

Can you name the only episode when we only hear Eddie's voice but never see him?

I think that Chester and Tooey were in a number of the second season episodes but were phased out when Eddie and Lumpy became popular in the third season.

Puberty?

I noticed that a long time ago, and have assumed it's either that Ken Osmond was quite awkward, especially in voice, for a while there, or that he had another performing engagement.

I guess there are other possibilities: he was recovering from a long illness or injury, there might have been a dispute (KO has said he "had a typical Hollywood mother"), or even trouble with the law.

Regardless, they kept Eddie's name in quite a number of episodes, indicating he would return some time. And when he does, he's a few inches taller and his voice has gone through the change, so I opt for the growth theory.

Can you name the only episode when we only hear Eddie's voice but never see him?

"Class Picture". Wally thinks he hears Eddie over the walky-talky, but he is really just outside.

Correct LaJonda! Remember I posed that question years ago on IMDB? I wonder why we never saw Eddie. I guess it was all about fixing the walky talky so he could talk to Eddie. Wonder if he was in the cast.