I drove from Chester to Chamonix this summer, with wife, 3 kids and my folks (4 bikes on the back). Tell him to man up…..
But to be a bit more realistic we did have a stop over half way which made it ok but I would suggest wasting 4 days traveling is not an option. Did the same drive the year before with my mates, straight trough 20 hours, 2 of us doing the driving, tough drive and the 2 of us where knackered the next day.
So either have a stop over, find a way to share it or plane.
Lastly, very jealous…..