Cradle of Vitality is a rare Enchantment card from Shards of Alara (ALA), collector number 7. Current market price: $0.53 (foil $5.93), TCGplayer market prices via Scryfall.
Whenever you gain life, you may pay {1}{W}. If you do, put a +1/+1 counter on target creature for each 1 life you gained.