Miles Isaacs was at a Shabbat lunch for a friend’s barmitzvah when another boy dislocated his arm playing football.

Concerned adults dialled 999. But when there was no response after more than half-an-hour, they rang Hatzola, the volunteer-staffed Jewish medical emergency service. The reaction was immediate.

It so impressed Miles, a year eight pupil at Immanuel College, that he donated £1,500 to Hatzola from gifts from his own barmitzvah.

Miles and his family, members of The Village Shul in Hampstead, visited Hatzola’s headquarters in Stamford Hill to see the defibrillator the donation had funded. 

Hatzola tweeted: “Kudos to this kind-hearted boy for his exceptional deed.”

Miles, parents Melodie and Stuart, brother Louis, 15, and sister Mirabelle, 11,  enjoyed a celebratory tea and a tour of the call centre.

Charity representatives also dedicated a plaque to its benefactor.

“They were so grateful to Miles and are just the most modest and kind people,” Mrs Isaacs said afterwards. “They left an unbelievable impression on him and our family.”