Family's Favor is a rare Enchantment card from New Capenna Commander (NCC), collector number 59. Current market price: $2.12, TCGplayer market prices via Scryfall.
Whenever you attack, put a shield counter on target attacking creature. Until end of turn, it gains "Whenever this creature deals combat damage to a player, remove a shield counter from it. If you do, draw a card." (If a creature with a shield counter on it would be dealt damage or destroyed, remove a shield counter from it instead.)