Cheshire Cat
The most curious thing..
Word on the interweb seems to be you could claim for it from your house insurance if you have liability cover, but he can't sue your son as he is a minor (I am not a lawyer and this not legal advice). He should be contacting his insurer for that amount of damage (assuming it is legit).
Personally I would tell him he needs to discuss it with his insurer.
https://forums.moneysavingexpert.com/discussion/2626563/7yr-old-crashed-bike-into-car-what-happens
https://forum.rac.co.uk/threads/173...I-have-to-pay-PLEASE-HELP?p=111396#post111396
https://www.mumsnet.com/Talk/legal_matters/818692-Car-hit-by-child-on-his-bike
https://www.balgores.com/what-are-my-rights-if-a-cyclist-damages-my-car/
Personally I would tell him he needs to discuss it with his insurer.
https://forums.moneysavingexpert.com/discussion/2626563/7yr-old-crashed-bike-into-car-what-happens
https://forum.rac.co.uk/threads/173...I-have-to-pay-PLEASE-HELP?p=111396#post111396
https://www.mumsnet.com/Talk/legal_matters/818692-Car-hit-by-child-on-his-bike
https://www.balgores.com/what-are-my-rights-if-a-cyclist-damages-my-car/