Wendy always attack Abigail with Y button

I play DS Shipwreck on Switch as Wendy, and she always have this option to kill Abigail in one shot. This is very inconvenient because when I try to help Abigail attacking monsters, I always hit her and she left me alone with horde of monsters. Ruin my game a couple times now.

Can’t find any Setting to change it. Bad design.