Who are these dolls?! What happened to Felicity, Josefina, Kirsten, Addy, Samantha, and Molly? Why d

Who are these dolls?! What happened to Felicity, Josefina, Kirsten, Addy, Samantha, and Molly? Why do all of their stories take place in the past century?

(Yes, I know I’m getting too worked up over this and that Rebecca is from 1914, but still)
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