John Conway’s author biography in Melvin Fitting and Brian Rayman’s 2017 book Raymond Smullyan on Self Reference:

John H. Conway is the John von Neumann Distinguished Professor Emeritus of Applied and Computational Mathematics at Princeton. He has four doctorate degrees: PhD (Cambridge), DSc (Liverpool), D.h.c. (Iasi), PhD (Bremen). He has written or co-written 11 books, one of which has appeared in 11 languages. He has both daughters and sons, each daughter has as many sisters as brothers and each son twice as many sisters as brothers. He has met Raymond Smullyan repeatedly at many Gatherings for Gardner and Andrew Buchanan in Cambridge, New York and Princeton.

The size of his family is left as an exercise.