Can you share game DLCs on PC without game pass?

Me and my brother are both part of a microsoft family, but neither of us are the parent account, because my dad has it; so we don’t game share directly with everyone else. I tried the method of going in and signing in with my account, downloading the DLCs for D2, and then he started up D2 on his microsoft account but the expansions did not transfer. is there anything else i can try or does he have to buy them?

:)