 It involves Grimoald and his son Childebert the Adopted taking the Austrasian throne from the true Merovingian King Dagobert II, son of the late Sigibert who died young at 26 years old.Historians like Pierre Riché are certain that Sigibert died in 656, having adopted Childebert due to his lack of an adult male heir.Following this, young Dagobert II was then exiled and tonsured by Grimoald and Dido of Poitiers, who then installed Childebert as King of Austrasia.