Second name? By that I'm assuming you mean his last name?
It's really irrelevant since there's no such character named Ralph on Family Guy.
However, there is the character, Ralph Wiggum on TheSimpsons.
Ralph Waldo Emerson's name is shared with his father, who was also named Ralph Emerson. The name "Ralph" was passed down through several generations of the Emerson family.
Meg
Angel City
Ralph Brooks's birth name is Ralph Thomas Brooks.
What are you asking? The name of the family? The name of the neighbors? The name of the dog? The name of the town? The name of the bar the guys drink? Please be more specific in your question so it can be answered properly.
Ralph Lauren was born with the Jewish name of Ralph Rueben Lifshitz
Ralph Bucko's birth name is Ralph Boukou.
Ralph Flanagan's birth name is Ralph Flanniken.
Ralph Forbes's birth name is Taylor, Ralph.
Ralph Rainger's birth name is Ralph Reichenthal.
Ralph McTell's birth name is Ralph May.
Ralph Meeker's birth name is Rathgeber, Ralph.