How Can Penis Length And Girth Be Increased?

Hi, may I answer your health queries right now ? Please type your query here...
                                             I was just woundering if their is a true way to grow your penis? I am only about 5 1/2in long and 4in girth erect and I know that my girl friend has had much bigger and its all in my head but im letting it ruin our relationship because I feel that im not big enough for her even tho she says it just fine.. I would really like to be atleast 7in long and 6in girth is this possiable? Thanks