HOW MANY SONS DID ABSALOM HAVE?

II Samuel 14:27 And unto Absalom there were born three sons, and one daughter, whose name was Tamar: she was a woman of a fair countenance. (KJV) II Samuel 18:18. Now Absalom in his lifetime had taken and reared up for himself a pillar, which is in the king's dale: for he said, I have no son to keep my name in remembrance: and he called the pillar after his own name: and it is called unto this day, Absalom's place.

Evidently, his three sons died before the events in 18:18.  Not a contradiction.