Keep in mind that it's a crime to deliberately withhold information from your insurance company. (valuepenguin.com)
And just like with tobacco use; it's a very bad idea to withhold information about your marijuana use from the insurance company on your application form. (myfinancialrevolution.com)
Assuming your brother truly knew nothing about his heart when he applied for insurance, then he did not withhold information on the application. (insuranceblogbychris.com)