In my Spanish class today, due to the fact it is St. Patrick's day we asked for a bit of Irish lore, and a bit of history on St. Patrick's. One thing led to another and my teacher gave us a short lecture on Cúchulainn. The information listed on this site states that he killed one of Culann's dogs by accident. Now, considering my teacher is also a somewhat noted college professor of archeology and I trust his words, he stated that Cúchulainn killed the dog on purpose because it was in his way. He also said that Cúchulainn killed many of Queen Medb's greatest warriors because she had an auroch female, and Culann had an auroch male. She wished for them to be bred, and so wrote a letter to ask if she could have the auroch bull. Culann said no which led Queen Medb to declare war, and Cúchulainn (due to the curse on Culann that restrained him from engaging in war for two weeks) who was at that time under Culann's rule, went out to face her army. He asked for the queen to send out her men one at a time, and she did and one by one he killed them for two weeks. Had Cúchulainn not been there Culann's land would have been taken by Queen Medb and she would have in the end gotten what she wanted, however Cúchulainn stood in her way long enough for the curse's affect to complete itself and Medb was driven back to her homeland with no auroch bull, and less men than she had when she departed.Cúchulainn also had a son with a fellow warrior hero woman, whom he named Cúchulainn (after himself). He placed a curse upon his son stating that he could never turn down a challenge, and that he could never reveal his name unless he was defeated in battle. Cúchulainn was traveling one day and he came across his son, and they ran into each other. He demanded that his son step out of his way or fight him. Unable to turn down a challenge, Cúchulainn's son accepted. Asking his son's name, Cúchulainn was of course turned down and after the battle was over and Cúchulainn had fatally wounded his son, his son was said to have stated, "My name is Cúchulainn, son of Cúchulainn." So in all, Cúchulainn killed his own son due to his unintentional curse upon him at birth.Of course any of this information could be incorrect, and please correct me if I'm wrong, but this is the information that I was given today in class.
Very important note - Irish people do NOT name their children Cúchulainn! :) It would be like calling your son Achilles or something similar. This name is completely associated with the hero in The Táin and no one else.
My Gaelic Literature professor this summer (in Galway, that might make a difference) pronounced this name: Koo-HUL-en with Koo as in "boo" and HUL as in "null".
The modern version of Cuchalainn is "O'Connell". The name O'Connell is believed to mean son of Culainn, and does not appear until Celtic times. Believed that the first ever bearer of the name was a son of Cuchulainn.