When a Dad appears in your dreams, if passed over, are typically signs of that person contacting you and letting you know they are ok. The spirit is also giving you advice, showing you solutions and showing you the other world feels and looks like.
Your dad will appear in your dreams when you explore the influences he holds over you during your life and how you are using his teachings to move forward. On the negative side, he may be showing his mistakes and not making the same mistakes. Your dad will also show you what is negative around you and help you with the emotions and emotional issues surrounding you.