We're getting ready to send out our save-the-dates, and I just came across a bit of an addressing dilemma. We're inviting the parents of one of my bridesmaids. Unfortunately, her mom just moved out (in December). They know I'm aware of the situation, so I'm not sure now whether I should find out where her mom is now staying and send a separate save-the-date there, or if I should just send it to both of them at their house (where her dad is still living).
They aren't divorced or even separated yet, and I'm not sure if they're in the process of that. I'll bring it up to my friend and see what she suggests, but I thought I'd post here in case there's some blatant form of etiquette I'm not aware of in a situation like this.
Thank you!

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