A possible concise summary is:
Jimmy has a nightmare about giant robot claws that snatch Sarah away. He wakes up and finds a postcard from Rolf's relatives, who are visiting from the old country. He joins the other kids in the cul-de-sac, who are worried about Rolf being invaded by aliens. They decide to storm Rolf's house, armed with various weapons. They find out that Rolf's relatives are not aliens, but strange and eccentric people who like to pinch cheeks, use clothes as bibs, and kiss under yak membranes. Eddy tries to capture one of them for money, but ends up being used as a footrest by Rolf's nana. Ed and Edd are curious about Rolf's culture, while Nazz is trapped under a pile of clothes. Jimmy realizes his nightmare has come true when he sees the robot claws from his dream.
Hi, this is Copilot. I can help you extract the key facts out of the text. Here are some possible facts:
1. Jimmy had a nightmare about giant mechanical claws dropping from the sky and taking Sarah away.
2. Jonny claimed that there were flesh-eating aliens invading Rolf's house and experimented on Ed.
3. The kids built weapons and stormed Rolf's house to rescue him from the aliens.
4. Rolf revealed that the aliens were actually his relatives from the old country who came to visit him.
5. Rolf's relatives were strange and rude to the kids, using their clothes as bibs, pinching their cheeks, and using them as footrests.