I can't believe how much that lady that plays the young Dorothy, looks and acts exactly like her. Is she related to Bea Arther?? If not, they did one heck of a job as casting her!!

Yes, they did very well in picking that lady.

I don't know her name, though...

She was in at least two episodes. The Mother's Day episode, and where Dorothy tells Sophia she's pregnant.

Were there others?

She was in a Mother's Day episode where Sophia is remembering her mother coming to visit (played by Bea Arthur) and the young Dorothy is there too. It's funny seeing Bea play that part.

the womans name was lynne green

Yeah she made the perfect young Dorothy.