Sarah gasped. Like Danny, she thought of Tommy as the young tearaway who’d settled down once he was given responsibility on the farm, and although if she’d added it up rationally she would have known how old he was, it was still a shock to realise he was well on the way to becoming a young man. ‘It doesn’t seem possible, Danny. Surely you don’t want that.’ She tried not to let her anxiety show, not only for Tommy but for Danny too. She knew better than anyone what he struggled so hard to keep hidden. Although technically now part of the Royal Navy, Danny had never gone – and could never go – to sea. All of the armed forces had turned him down, despite his obvious courage and willingness to sign up, as rheumatic fever had left him with an enlarged heart. Any extreme physical activity would put him at risk. They’d only found out when he’d stood in for a fallen fireman at a vast blaze down at the docks. Danny had taken the man’s place without hesitation but had collapsed afterwards. Sarah had rescued him but the news had got out. When it came to fighting for his country, Danny Callaghan was damaged goods.

By a stroke of luck, Danny had shown an uncommon aptitude for solving puzzles and crosswords while recuperating, and this had led to him being recruited to join Western Approaches Command, as they were in desperate need of that rare kind of skill to help decipher enemy signals. Frank Feeny worked there as a naval officer, and had recommended his old friend, against some opposition from the more traditional superior officers. Danny had only ever worked down on the docks up till then and had been a tearaway himself when in his teens.

This was exactly what was on Danny’s mind as he reread his little brother’s letter. He recognised that feeling of wanting to join up, do his bit, and also see the world and test himself against the odds, take a risk and worry about the consequences later. It was precisely why he wanted to protect Tommy from it. Now he was older, he wished he’d paid more attention at school, but at the time he couldn’t be bothered, couldn’t wait for it to end so he could get out and live his own life. It had meant that his work at Derby House had been extra hard to begin with as he’d had to learn so much from scratch. He could see with hindsight how he would have benefited from listening to his teachers when they’d insisted he could have gone further. All right, the family had needed him to go out and earn his keep – but he’d wasted the last year in the classroom. He wanted better for Tommy.