American Express has sent out mailer offering 20,000 Membership Rewards (MR) points after you add an additional card member (authorized user) to your account, and they spend $2,000 on their new card in their first 6 months of card membership.
This particular targeted offer expires on 2/18/2022 but American Express is known to send out these offers on periodic basis.
Closing Thoughts
I got this on American Express Platinum card but adding authorized user to platinum card costs $175. Not a bad offer.