Original: Their first-born son died as an infant in 1936 , their second son , John ( born in 1939 ) contracted polio , and their daughter , Shirley , born in 1941 , had cerebral palsy since her birth .
Simplified: Their second child ( John , born in 1939 ) had a health problem called polio and their third child ( Shirley , born in 1941 ) had cerebral palsy since birth .