This is a jo..... Legitimate Theory that Pikachu is the father of Butterfrees children and here is my proof.
-Pikachu babysits and feeds them even causing them to evolve on occasion
-Pikachu and Butterfree are seen hanging out on the title screen
-Butterfree holds the pinata for Pikachu
-Pikachu is not with his kids because he wants to make sure you never go and catch them so thats why he babysits them so you can't catch them....i think
So thats why i think Pikachu is the father of Butterfrees kids. Don't believe me then play the greatest game of all time "Hey You Pikachu" for the N64
Gerald the Theorist solving the world of pokemon since 1996.