From Longman Dictionary of Contemporary Englishgrown children/daughter/songrown children/daughter/sonchildren etc who are now adults I’ve got two grown daughters and a son. → grown
Examples from the Corpus
grown children/daughter/son• Seeing photographs of Rubilove Willcox Aiu in newspapers last Sunday was unexpected and bewildering for her grown children.• Tall, slender and divorced, Sheila had-incredibly-two grown sons.• See more of his grown daughter and son.• I had two grown daughters, and when I lost the first one, this one became the apple of my eye.• Yet her husband, laid off from his job as a messenger, and her grown children are unemployed.• The senator, 72, has a grown daughter by his former wife but is of grandfatherly vintage now. 