Unfortunately, you can't claim a deduction for student loan interest unless the loan is in your name or you are a cosigner.
You can claim the deduction only if you were legally obligated to pay interest on a qualified student loan. ”Legally obligated” to pay interest on a qualified student loan means you either signed for the loan yourself, as the student; or you cosigned for the loan as a parent or other cosigner.
See "Can I claim my student loan?" for full details:
https://ttlc.intuit.com/replies/3302319
