Grey was the son and heir of Elizabeth Ferrers,
6th Baroness Ferrers of Groby (1419–1483) and of Sir Edward Grey (c. 1415–1457), a son of
Reynold Grey, 3rd Baron Grey of Ruthin. After the death of Grey's father in 1457, his mother married his stepfather,
John Bourchier, in 1462; he assumed his wife's title, Baron Ferrers of Groby. As Grey predeceased his mother, Lady Ferrers, the title of
Baron Ferrers of Groby passed to his eldest son and heir,
Thomas. Grey was never summoned to Parliament. Another title,
Baron Grey of Groby, was created 21 July 1603 for his direct descendant,
Henry Grey (c.1547–1614). On the death of his father, John inherited the title of
Baron Astley from his father, who inherited it from his grandfather, which his son would inherit on his death. ==Wife and children==