OMG how devastating for you and Muffin..
Big cyber (((((((hugs))))))) to you...
Muffin will just get on with her life... clean herself up and act like nothing has happened...
sadly thats nature for you...
its always a mystery why these things happen- more so when they seemed perfect for each other.. It just rocks your world terribly at the time
I lost a litter of rottweilers once the same way..
its still gives me a heavy heart to this day

I would try the mating again
you never know, she is very likely to have a lovely litter for you next time
I have known very close matings to be fantastic
let us know what you decide xx

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