In Stitches Meaning

(idiomatic) Laughing vigorously; very amused; aching due to convulsive laughter.

Example: 1918, Laura Lee Hope, The Outdoor Girls in Army Service, chapter 15:
  "I was just dancing with old Doctor Riley, and he kept me in stitches. Half the time he had almost to carry me around, I was laughing so."
1955 May 15, "People", in Time:
  Leaving the White House after a unilateral chat with Coolidge, Actress Barrymore, in stitches from laughter, was confronted by perplexed newsmen wondering what was so funny.
2004, Willis Barnstone, We Jews and Blacks, ISBN 9780253344199, page 59:
  I took a graduate seminar in close-reading of Dylan Thomas and Joyce, and among the smart students a nun and a rabbi kept us in stitches with their endless whimsy and scholarship.