We receive the Holy Spirit at Baptism, and get 'booster shots' all through our lives from the other sacraments. It is your love that helps him when he gets discouraged with his homework or has trouble with his friends. The Love of God, in the Person of the Holy Spirit, helps him the same way if he remembers to call on it with a little prayer. In the same way a child remembers the good dinners people have made out of love, a child can remember the Eucharist, and know that God's Love is with him. God is like food.
Food tastes good, looks good and smells good.
I wouldn't want to eat food that tasted good, but smelled bad, or had no smell at all. In the same way, God isn't God without all three Persons. Food also nourishes us with protein, carbohydrates and vitamins. All of the nutrients in food are essential - without protein we can't build muscle, without carbohydrates we won't have any energy and without vitamins we can't stay healthy. Since the Holy Spirit is God's Love and is with us at all times, we should remember His presence and call upon HIm at all times.