The Best thing to do is go to their website and check your dates. They maintain a complete list.
The mummy exhibit
Union station is always decorated for Christmas with trees and things and the miniature trains are part of it
The miniature trains are always there I believe.
After looking at their events calendar, it doesn't look like any special displays will be up during that time
They are already putting up Christmas decorations, they have one of the best displays in the city.
Google it
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