Take one anxious dog who needs a loving home and family.
Add a suitable home, with children who are keen, but a little wary.
Leave to get to know each other for a week. Note: there may still be some wariness and anxiety visible at this stage.
When the mixture has stewed, add in a long car trip, a caravan site and some beaches.
Observe: an exhausted, running dog. Exhausted, happy, running children. Laughter, relaxation. If all goes well, the children may finally be allowed to pet the dog without him backing off.
Result: Progress. Hurrah!