What is the flashback Penelope has to when she was nineteen?

Penelope remembers what life was like when she was nineteen. She is with her family at Carn Cottage in Porthkerris for the holiday and waiting to hear if their country is about to go to war. On the way to find her father at his studio, she hears that they have entered into war and goes to get him. Sophie, her mother, has told her to bring her father directly home and not let him go to the pub today.