I could be off base, but it sounds like the son-in-law, while he would be the borrower, he would also be a "co-signer" as defined by Regulation AA (227.12), meaning that he will not receive any benefit from the loan proceeds. Check your loan policy. Some banks' policies state that they don't do loans to cosigners. If you do allow cosigners, be sure to include the Notice to Cosigner disclosure (227.14).
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