In some cultures, "father" represents authority or powerful. He's the head of the family and he's expected to be strong, tough and responsible. He's a figure of righteousness and productivity. He is expected to make correct decisions and bring prosperities to the family. I guess that Jesus wants to remind us that we can expect something more from our fathers, both earthly and heavenly. Abba brings loving care, protection, security and trust. When we encounter problems in life, Abba has a way out. He is wise and He's got solutions. But we need to call out for Him first. He is always there. His love is faithful. He looks after his children and we're all His little princes and princesses.