Eitri. Ragnar spoke his father's name simply to his youngest son, staring unseeingly into the distance. Of course Eitri was true to his heathen roots too — after all he had knocked up a slave and fathered Dagrun while he was still alive and Kenna hadn't, as far as Ragnar knew, paid much attention to it. You can call them whatever you are comfortable with, Ragnar would not presume to tell his children what they should call their ...siblings (even Ragnar wasn't sure what they would realistically be considered aside from step because they're not half). Tveir asked him for confirmation that he would make a good warrior and for a moment Ragnar was silent, contemplative.
He had seen Tveir play with Ein and Gyda but that was a wholly different thing from being a true warrior. Without seeing how Tveir took to the training and how he applied it to real life situation Ragnar had no real answer for him. He did not know if Tveir could actually kill his opponent or not. He was almost too much like Thistle, as far as Ragnar could currently see — but you ended your enemy, either out of respect for them to put them out of their suffering, or because if you didn't they would spring a surprise attack on you. I think that you will be good at anything you want to be, as long as you are willing to put in the hard work. It wouldn't be easy because life wasn't easy and Ragnar wouldn't hold anything back. He wanted his sons to survive in the world outside of the Bay and they would have to give back everything that was thrown their way and then some. He spoke only to encourage his young son, yet at the same time did not want to fill his head with false illusions. Ragnar was not a huge fan of lying through he had done it before.