Sister's house in probate after death. Many questions

Sister passed January 28, 2022. Sister said house in probate. Says she had no health ins. And house is being sold to pay medical bills. She worked for Lockheed and McDonnell Douglas and had great health ins. I think my sister is up to something. How do I check this out. I'm in ca and plan on coming out may 1, 22. How do we get the ball rolling in getting the details?