“It’s best to have it done at birth...”
This sounds like two vindictive adults who had a child, broke off their relationship and are now using this poor boy to “up” the other parent. Years back when we were looking into foreign adoption, we asked our pediatrician about circumcision and older children (18 months and above). The practice said if it had not been done by age 1, they would refuse to do it UNLESS there was some sort of medical issue like what you described or numerous UTI’s. The child could make up his own mind and have it done in his later teens (and under anesthesia). Newborns don’t have the same nerve endings as older kids or grown ups. Many newborns literally sleep right through it.
This may explain the rage of Moslem men - they get it at age 13.