Legal Question in Workers Comp in California

Assuming they work more than just a few hours every month, you do need coverage and it is probably worth the extra cost. You have to check whether your own medical insurance that covers them, if it does, requires WC to cover the costs of any industrial injuries. Call your WC carrier and ask the employer rating department how much more it would cost to include them. It likely will not be that much.

Family members must be covered as well. And besides, why wouldn't you want to cover them?