Emmerdale viewers were left horrified over Arthur's nasty behaviour tonight, branding him a "demon child".
Arthur ended up punching Archie - after saying that no one missed his mum now that she was dead.
Ever since Archie appeared in the Dales, Arthur has clearly been jealous of the attention he has been getting from Laurel.
And he continued to secretly lash out at Archie tonight, telling him that he wasn't welcome to the picnic for Ashley's birthday.
When they got back later, Archie was in the pirate ship with Arthur, who began saying spiteful things about his mum.
Arthur ended up punching Archie, leaving him lying on the floor, but covered it up by saying that he had just fallen over.
Afterwards, however, Jai and Laurel noticed Archie's bruises and Arthur falsely accused Jimmy of being responsible.
And viewers were stunned by Arthur, slamming him for being "awful".
One tweeted: "Whoa Arthur! Really becoming a little demon child now! #emmerdale."
While another commented: "Arthur savage bruh #emmerdale."
A third remarked: "Poor little Archie... Arthur’s a bully... #Emmerdale."
"Never liked Arthur but he has completely gone off the rails, horrible little boy #emmerdale," another fumed.
*Emmerdale returns tomorrow at 7pm on ITV
