Laxman Kumara was the only son1 of Duryodhana and Bhanumati. He battled in the Mahabharata war and did perform many acts of bravery, like saving King Bahlika, killing Shikandi's son, etc. He was later killed by Abhimanyu (who was killed on the same day).
However, what interests me is the proximity of his name, "Laxman Kumara", to that of Lord Rama's brother, Lakshmana. Are there any mentions about him being named after Lakshmana, or about how they chose his name?
1(they had another daughter, Lakshma, who was the wife of Samba, son of Lord Krishna)