How can a 13 year old get proof of vaccination?

[loveandroses]

DS was vaccinated a month or two ago at school. Unfortunately he has lost the "record card" they gave him that proves this. He has since had covid as well. He is due to perform in a care home in a couple of weeks and they, understandably, want proof that he is vaccinated. As far as I can tell he can't use the NHS app because isn't old enough. How can he provide proof?

It will still show on his medical records, can you ask the GP surgery to print out his immunisation records? I do this for children when the parent has forgotten the red book, it only takes a minute.

Thank you. I called the GP surgery and they are happy to do that!