Sorry, I should have added: I am in Texas. And, I've experienced this exact issue: family members with a driver's in the same household are presumed to have access to the vehicles.
I don't know if it was required by law, or was our insurance company's policy. But, since it was a temporary situation, I didn't pursue it.
It was your insurance company's policy - not Texas law.
Sorry, I should have added: I am in Texas. And, I’ve experienced this exact issue: family members with a driver’s in the same household are presumed to have access to the vehicles.
I called other companies to try and get a policy without my 18 year old son but everyone I called gave me higher prices because of my 18 year old son.