There are various ways we could have managed this. We did contemplate a train or plane journey to Glasgow then renting a car, but with car seats, travel cots etc., it was just easier to take our stuff with us in our own car. Plus it’s a much smaller carbon footprint.
That decided, how to tackle a 9 hour journey with the kids? Travel all day with plenty of stops and play breaks? Overnight driving? In the end we tried it two ways…