No, Niro is suspected as Lunadel's and Khundun's son. He is half-elf, like Lunadel, Evan is not half-elf he's completely human which means Khundun is his father but his mother is human. We don't know who's Evan's mother.
His mother must be selfish and have high pride issue like him or else the father is really cool and mature. No wonder he is not exactly like his father who is so great
The thing is it's weird the way it was presented, we can see why Niro is Khundun's and Lunadel's son but... we have no clue about Evan. My theory is Khundun had a wife before the whole ordeal war happened and before he left to fight he left his wife pregnant with Evan... then had a romance with Lunadel... otherwise it wouldn't match up with what we're being told.
Yea, it's totally a weird concept and it's frustrating we have to wait to know it too. Ughh
I think Lunadel was carrying Evan at this time period. Kundun probably ended up getting consumed by that red stone thingy, so she was heartbroken and yadah2 somehow ended up with Muren. And THEN did she have Niro.
Or Evan and Niro might be twins, but that sounds the least possible theory ╮(￣▽￣)╭