It's pretty straightforward, in your AlbyHib go to the App Store and open the Friends and Family app up, put in the name of the person and it gives you several onboarding options (you need to choose one right away, as the onboarding options are only shown once. You can delete and recreate the family wallet if you aren't ready yet). I just did it with Alby Go mobile app and once you scan the QR it lets you choose a new alby lightning address.

https://image.nostr.build/acc2bc42769f0b559ece19e9b8fd63b01793e5453667652dfc02405d23920b26.jpg