[1]We hope that the lack of stimulation hasn't been 'imprinted' on her.
She is still young, I am sure she will remember how to play.

[2]We are wondering if the two sisters will recognize each other? Possibly not, but they are both babies and should be happy for a playmate Will one become more alpha or is this not the case with females? Females can be very ALPHA, and no doubt one will dominate the other. But this is normal.

[3]We've never had two cats. Will they keep to themselves or bond with the humans? Will both go to one human or will they each have their own human?
Just depends on their individual personalities. The good part is that tey will always have each other for company/play.

[4]Also, our current Mau is a talker. We are hoping that having another Mau around will occupy her and maybe even quiet her down a bit. The E. Mau, as an oriental type breed, is usually talkative. And cats talk to their humans, not to each other. So, again, she may or may not be a talker, but she has a good chance at being chatty due to her breed.

[5]We know a lot of the readers on this thread have multiple cat households and we're posting because we've always had just one. Any and all thoughts will be greatly aprreciated.

I think you will be glad that you got the 2nd kitten. Makes life better for all.