After the Second World War the government decided it was a good idea to make 10 year olds sit an aptitude exam. If you passed you went to grammar school and had a chance of going to uni and/or having a decent career. If you failed you went to the thick people school and were written off for life. Most of England and wales have long since abandoned this as ridiculous as you can’t make a reliable judgement on a 10 year old based on one exam but certain areas (Essex, Buckinghamshire, Kent etc) still make children go through this ordeal.
Consequently most parents in 11+ areas have been privately tutoring their kids since they were 5 to pass said exam so her “he had his 11+ thing haha” speech is bollox if she has any iota of concern for his education as he will have been preparing for this for years.