They can be candle light, though it small it can give you a hope and the small candle light can help you to overcome the darkness. Like a candle they will melt themselves to give to a light. If you choose the right person in your life they can bright up your life with light from dark. It can be the light in life forever.
They can good angel and worst devil, it depends on how you treat them. They can be the light in life forever. They can protect you, they can heal you and even they can destroy. But never underestimate them.