Giving an Adult Chao a Heart Fruit will cause it to go into its mating season (A ring of flowers will surround the chao.) allowing it to breed with other adult chao. However, if a child chao eats this fruit, it's lifespan will decrease slightly. After when the two chao mate they both have a egg which you can hatch and raise. However, nothing will happen if the garden you use the fruit in is full.