There's that fear monster lurking again...must be old man Winter playing his usual tricks.
Here's a suggestion on how to approach W with S12's situation. Why don't you call a family meeting or while have a family dinner? Then perhaps do what the Obama's ritually do during dinner time...what were the day's "roses" and "thorns"? Perhaps this will give S12 an opportunity to express his feelings about W and it will give you some 'cover' from W in that she can't target you directly.
One way to gently broaching the subject is to discuss your own "thorns & roses" first and then look to S12 to say "how about you?" Then go around the table to the next person.
