Did they just bring Lori in because they were running out of ideas or was it some sort of way to show what it would have been like it the Douglases had a kid?

I see you have been watching the evening showing on TV Land this week (so was I), I think the producers may have been considering adding another character. The show had a following among younger children of that day because of the Arnold character and they may have wanted to build on that.

I don't think the character worked in the Green Acre universe where Oliver was subjected to some rather unique menu items from Lisa (I think the audience might have been a little more concerned if a young child was sitting at that table).

Green Acres is my favorite show of all time.
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