"Down by the River" is the second segment of the sixty-first episode of Star vs. the Forces of Evil. It premiered on March 24, 2019 alongside "Yada Yada Berries", and is the second segment of the fifth episode in the fourth season.
The Maizley family return to their home only to find that it is now inhabited by Monsters. They refuse to accept the fact it was always a monster home despite the fact that the house is clearly built for gigantic proportions. The Monsters have nevertheless collected of their belongings and politely tell them to leave. Meanwhile in the woods, Moon and River have built a well furbished yurt for them to stay in. They have become incredibly bored and do not know what to do with themselves. The Maizleys arrive and ask that Moon do something to get their home back, but she tells them that she is no longer queen and therefore it is not her problem anymore.
The Maizleys move in next door to Moon and River and proceed to bother them with their laundry and chores. They indirectly harm River with dangerous poisonous eggs and begin to slowly annoy Moon who is trying to remain as cordial as possible. She is finally driven over the edge when the Maizleys arrive in the middle of the night with pots and pans, making noise to scare away the "Hookman". Moon finally breaks down and angrily tells them to leave her property. The next morning, Moon has made numerous counter measures to attack the Maizleys should they come back. Moon and River wait, but see no sign of them.
Moon and River go out into the woods and find the Maizleys sadly walking away. They confront them and reveal that they got lost in the dark and ran into numerous obstacles and hazards as well as the Hookman. ("Oh, it was terrible. He hooked us into buying homeowner insurance.") They further admit that they have never learned to take proper care of themselves because Moon did such a wonderful job taking care of them. Realizing that the Mewmans still need her, Moon and River take it upon themselves to aid the Maizleys into adapting to simple life. Later, another family arrive asking for help, pleasing Moon and River.
- Grey DeLisle as Moon Butterfly
- Alan Tudyk as River Butterfly
- John DiMaggio as Merrick Maizley
- Donna Lynne Champlin as Maude Maizley
- Madeleine Curry as Mendel Maizley
- Hudson Wet as Manny Maizley
- According to the Mewni calendar, this episode takes place in the 1,753rd "Year of Great Bounty".
- Moon's exploding pies may be a reference to the SpongeBob SquarePants episode "Dying for Pie".
- The episode's title is a reference to Matt Foley, a character played by Chris Farley on Saturday Night Live, who often described himself as "living in a van down by the river."
- May 10, 2019 (Southeast Asia)