Suspect it wouldn't be possible as there would probably have to be a match on names. You can however (well depends on your CC provider of course) have one primary account owner, and have multiple supplementary cards and have all points pooled together to the primary card holders FF account.
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Those are 2 slightly different questions. It is possible to link multiple credits cards to one account provided the names match. e.g. I have 3 credit cards, in my name, linked to my QFF account. I doubt you can link someone else's card to your account. Either supplementary cards on your account will work, or transfer the points from your wife's QFF account to yours.