LOS ANGELES—Willie Garson, who played Stanford Blatch, Carrie Bradshaw’s friend on TV’s “Sex and the City” and its movie sequels, has died, his son announced Tuesday. He was 57. “I love you so much papa. Rest In Peace and I’m so glad you got to share all your adventures with me and were able to accomplish so much,” Nathen Garson wrote on Instagram. “I’m so proud of you.” “You always were the toughest and funniest and smartest person I’ve known,” his son added. No details of his death were released. Messages seeking comment from his representatives weren’t immediately returned. Garson portrayed Blatch, a talent agent and the devoted best male friend to Sarah Jessica Parker’s Carrie for six seasons. He reprised the role in the films “Sex and the City” and “Sex and the City 2,” and had been filming an upcoming series revival for HBO Max called “And Just …