Little Dipper's Links
Dipper knows his siblings sternness comes from a place of love, but wishes that Umbriel would stop mother henning him. He already hears enough about his love for the devil's lettuce from his mothers and father.
Umbriel is strongly disappointed in Dipper, he thinks he's lazy and incapable of getting out of his own way. He wishes he would pull his head out of his ass and realize that he's a prince and his public image matters. He can't be out stoned all the time with his friends!
Dipper likes his little sister, but struggles to interact with her outside of dinner and family game nights. (These are mandated by Twilight btw, Luna and Mac also don't particularly like it, but love Twi and put up with it.) They usually end up joining teams with Momma Luna and going after Umbriel and Starfruit's team though, so they at least have their family game night rivalry.
Starfruit and Little Dipper have a distant relationship, they don't dislike one another but they don't have a lot in common outside of being siblings. She thinks he's a little weird and stays out of his way.
Dipper thinks that Constance is doing the supervillain thing as a bit and thinks it's super cool how she doesn't ever break character.
Constance and Little Dipper are really, really different. Personality and appearance wise. Their parents find it odd due to them sharing a parental pair, but things happen! Constance really doesn't know how to interact with their brother, Dipper. She finds him to be a little bit boring, not nearly like Umbriel though.