Did you ever consider that your daughter and son might be suffering for your SIL, and sharing in the sufferings of Christ, not as a negative thing, but as a positive spiritual growth coming closer to Christ is their lives. A hard thing to understand, but true, it’s called being perfected, or purged. One can be lulled into a comfortable life, and have spiritual sloth. There is a saying " Nothing happens that is not permitted by God. The message could be a conscience diversion to your SIL , a type of superstition and Christians know who is active in these situations As a teacher he must have some intellectual acumen, and I don’t believe there are pure atheists, or agnostics. God instilled in all of us a desire to know the truth, even a liar doesn’t want to be lied to. There is always hope, keep on praying, and offer up some of the suffering for your SIL.
