How can I get to the bottom of this?

My children live on the other side of the world. A few months ago my son told me that he thought his dad was “losing it” and “going crazy”. Specifically, going into angry rages about minor things. He told me that he and his sister had convinced him, (their dad) to see a doctor about “his moods”. “Screamed into it” is how my son put it. Now, both my kid’s computers are broken, and my ex, (their dad) told me my daughter “allowed’ him to read an email from me. He also said that she is now “using his computer so it isn’t an issue that theirs are broken”. I have heard nothing from my son since. I am wondering if my ex found out from reading my daughter’s email that I know he went to a doctor about his moods, and if my son is afraid to contact me now. I paid for both of these computers and pay for their internet service. Whenever I ask what happened to their computers, I get a murky answer. These kids are 14 so it’s not like they’re too young to take care of a computer. Is there some artful way I can put it to find out what happened?