A possible concise summary is:
Junior and Jeffy want to have a baby together, so they ask Cody to invent a machine that can impregnate Jeffy. Jeffy gives birth to a baby boy named Jeffy Junior, who causes trouble and destroys their toys. Junior and Jeffy decide to give him up for adoption to a man who wants a kid who can make an iPad. They regret their decision and miss their son.
Here are some possible facts extracted from the text:
1. Jeffy is a character who picks his nose and wipes his boogers on the couch.
2. Junior is a character who wants to have a kid with Jeffy.
3. Cody is a character who invents a machine called the impregnator that can make Jeffy pregnant.
4. Jeffy gets pregnant with Junior's spit and gives birth to a baby named Jeffy Junior.
5. Mario and Rosalina are characters who mistake the pregnancy test for Rosalina's and think she is pregnant.
6. Jeffy Junior is a destructive baby who breaks Junior's golden Thomas and Jeffy's cat piano.
7. Junior and Jeffy decide to give up Jeffy Junior for adoption to a man who wants a kid who is good at making an iPad.