"The Dark Side is strong and tempts us all, Luke. There is no shame in admitting such a thing. Rather, it makes your commitment to the Light that much more admirable," Obi-Wan reassured the other man, then listened as he continued to talk. The information that Luke had named his son for him was beyond touching, and he couldn't help the sudden smile on his face at the news.
"I know some of what happens," he admitted, not wanting to share the existance of the holovids with Luke just after his arrival. Perhaps when he was more settled, he would explain. "But not much. I was told of what happened to Alderaan, and the Death Star. Both Death Stars, actually. I know you trained with Master Yoda on Dagobah, and that An... Your father. I know he... He turns back to the Light. Thank you for doing what I could not."
Smoothing down his beard, he took a moment after that to centre himself in the Force, and then answered the rest of Luke's questions. "I have not met any other Skywalkers, no. If Leia or Han have been here, I was not on this island at the time. They have children?" Given that Luke seemed to be from a different timeline than Poe, Rey and Finn (and therefore Kylo Ren as well), it seemed prudent to work out who Luke meant by Leia's family, instead of announcing to him that he had a brand new nephew.