My Grandad looked like Merlin. He had white hair down to his shoulders, steel-blue eyes that sparkled when he grinned, and half his teeth.

My Grandad worked as an engineer during the war. He used to talk about the bombers, who always claimed they were able to hit a target, even though my Grandad pointed out that the practice “bombs” they were dropping hadn’t actually fallen into the nets he’d put in the targets. It was, he said, the only way to test whether they were telling the truth. He was a keen physicist, mathematician and astronomer, and had a marvellous fascination with history and pretty nurses.

In the last few years his memory, and his body, started to fade. He stopped being able to hold on to conversations, but still enjoyed doing the crossword. He read books and papers. He loved to drink whisky and eat sweets. The last time I saw him, we brought him some jellied fruit. “No thanks, Grandad,” I said. “You have them.”

“Oh, good,” he grinned, and hid the box. I never saw a smile on his face that wasn’t a grin – cheeky, half-mocking, and often poking gentle fun at my ever-patient mother. That’s how I’ll remember him; by that smile, and the sparkle in his eyes.

My Grandad passed away in his sleep last night. He would have been 98 next month.

Sleep well, Grandad. I love you. Thank you for making my world a better place.