After almost conquering all of England, Scotland was torn apart by civil war and I'm reduced to being a 6 year old Duke under a regent

.
Regardless, we're being invaded by England backed by France and separately by the Isle's.
Before I call up my levies and put them on a sacrificial altar, is there a way to see WHAT they're invading for?
If all they want is one or two lousy provinces that aren't mine, why bother!
Thanks!