did he have any children ?
Yes, three children
Galileo Galilei
fathered three children 
did the maya invent their own version of gunpowder UNANSWERABLE who is galileo galilei? Astronomer, physicist and engineer
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Galileo Galilei [SEP] Children
Despite being a genuinely pious Roman Catholic, Galileo fathered three children out of wedlock with Marina Gamba. They had two daughters, Virginia (born 1600) and Livia (born 1601), and a son, Vincenzo (born 1606). Because of their illegitimate birth, their father considered the girls unmarriageable, if not posing problems of prohibitively expensive support or dowries, which would have been similar to Galileo's previous extensive financial problems with two of his sisters. Their only worthy alternative was the religious life. Both girls were accepted by the convent of San Matteo in Arcetri and remained there for the rest of their lives.