Grant land as bribes for the influential Gaelic lords. This ought to curb any petty squabbles. Also to save face, you may need to reconsider Ewen's position as ruler within the Isles.
Leave Ewen in control of the Isles and get on with more pressing affairs in Norway. He, if anyone, will find a solution to the problems. Anyway, you need to turn your attention to affairs in Norway.
The kingdom of the Scots is in a vulnerable position. With a ruler of only six years of age, you could exploit the situation. Strike into the heart to gain more land and unlimited power.
Which card will you play?