Thank you, thank you for your feedback on sharing!

I was blessed to find some new terms and ideas for our strategy on tackling this unending battle. I'd like to highlight a few on this post that we will be implementing into our sharing "situations":

Labeling shared items as "Family" items. I always felt funny saying, "this is yours and Everett's"... when I'm the one navigating who can play with it, also, what happens when Nolan or Georgia comes? (some inside info for potential future names of our offspring :-)).
Counting--I always say "two minutes", but counting goes by quicker and the child can understand that at 18, they will soon have to part ways.
Special toys--I agree that there should be allowance for special toys, but the judgement on when to bring them out or where to play with them should be guided (ie: not at a playgroup!)
Practicing outside the heat of the moment. We do this a lot with other behavioral training, but sharing I'm embarrassed to say we haven't so much... I'm going to have to get creative on fun things we can do with the most possessed toys to help with sharing. This has always been very effective for us.

Thank you so much for your feedback. More is welcomed and I hope the other moms out there that are dealing with this issue will get some great ideas from here. Love this sisterhood of maternal advice that silently exists. It's a beautiful things, ladies. Let's embrace it!