Buyer and Co-buyer car insurance responsibility

Hi,

I just helped my son and daughter in law purchase a car. I am the "Buyer" and she is the "co-buyer". Can the insurance be put on either policy or is the Buyer responsile to insure the car?
Please help.

Thanks!

I didn't find the right solution from the Internet.

References:http://www.insuranceforum1.com/showthread.php?t=94379

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