Elrond had to exercise all of his self control to resist the urge to sigh loudly as he walked into the room and saw his children. All three of them were there, gathered around the families dining table, eating in silence and refusing to make eye contact with each other.
They each glanced up briefly when Elrond walked in before quickly looking back down to their food. Elrond carefully schooled his face into neutrality before walking over and taking his seat. A cursory glance revealed all that he needed to know. Judging by Arwen and Elrohir's bitter expressions, they'd been arguing recently. And judging from the way Elladan listlessly pushed his food around, and the unusual distance between the brother's seats, the twins had not taken the same side on whatever the matter had been.
He let them stew in silence for a few minutes longer while he ate serenely, enjoying the uncommon moment of silence in his house. Finally though, he decided he probably ought to do something, and set his food aside. All of his children glanced up at the sound, and each of them froze in turn upon seeing him sitting there, the picture of serenity.
"Ada…?" Elrohir began cautiously, but Elrond silenced him by raising one hand, still smiling peacefully.
"Did I ever tell you that we're cousins?" he asked, sweetly.
Elladan promptly choked on his food at the unexpected statement. Arwen simply sighed and raised both hands to her temples.
"This isn't going to be another story about the bird, is it?" She simply asked, realizing they were in for yet another lecture about Elrond's family - this was his solution every time his children had a falling out. Distract them or confuse them, or both. And nothing did so quite so effectively as talking about his family.
Elrond scowled. "No, this isn't another story about the bird."
"Now," he leaned forward and steepled his fingers together, resting his chin on his hands. "Let's see if I can get this in one go."
So I'm pretty sure that would make him their uncle."
"Celeborn was the bird's uncle?" Elladan whispered to his brother in confusion. Elrohir shrugged back, having not followed the story very well so far. Arwen was scowling at them all in silence.
"I'm not talking about- she wasn't a bird, okay? Just forget I ever mentioned a bird!" Elrond huffed. "So long as I'm not mistaken, Celeborn was the uncle to her and her brothers-"
"The bird had brothers?" Elrohir asked, sitting up. "You've never mentioned that before."
"Hadn't I?" Elrond wondered, before quickly shaking his head. "In any case, that's a story for another time. They're not really important."
"Not important?"
"Er… they didn't do much."
His children exchanged puzzled glances but Elrond continued before they had a chance to interrupt him again.
"Yes my mother had brothers. I'll tell you about them later. In any case, if Celeborn was their uncle, that would have made him my great uncle."
"Celeborn is your great uncle!?" Elrohir squeaked in alarm.
"... Probably."
"But I thought he was your father in law?" Elladan probed, cautiously. He knew better than to let himself get drawn into one of these discussions, but his father had a habit of making staying out of them very difficult.
"He is." Elrond nodded. "Obviously, he is Celebrian's father, which in turn makes him your grandfather."
"If Celeborn is you're great uncle, but also naneth's father, then doesn't that make naneth a generation above you?" Arwen asked.
Elladan nodded and spoke up before his father had a chance to. "It does. But more importantly, it would also make nana his cousin."
Both of his siblings paused and turned to look at him.
"It would?" Elrohir questioned. "Are you sure?"
Elladan nodded. "She would be his first cousin, once removed."
Elrond smiled, apparently pleased. "It's good to see you've been following along." He didn't seem at all troubled by the fact that he'd apparently married his cousin, but then again, he'd probably had a few centuries to come to terms with it.
"I'm confused, adar." Arwen confessed. "As…. interesting as that is, how does any of this possibly make us your cousins?" she made a slight face.
Elrohir turned to his brother, hoping he would have an explanation for this as well. But, after holding an expression of extreme focus for a few minutes, Elladan finally gave up and shrugged. "I'm afraid I've finally gotten lost as well." He admitted.
Elrond sighed as he began to recap quickly. "Celeborn was Elwing's uncle. Elwing was my mother, making Celeborn my great uncle. This means that Celebrian is my first cousin, once removed. After marrying her, Celeborn became both my great uncle and my father in law. Now, the grandchildren of one's great aunt and uncle would be that person's second cousins. Seeing as Celeborn and Galadriel are my great aunt and uncle, and you are their grandchildren, that would make you my second cousins." He leaned back in his chair once more, folding his hands together on the table, the serene smile never once leaving his face.
"But…." Arwen twitched.
"But you're our ada!" Elladan choked, knowing he should have left the moment Elrond began to expound once more on his family tree. It was a practice which only ever ended in disaster.
"Adar!" Arwen cried despairingly. "Can you be sure of this?"
There was a long pause before Elrond finally, begrudgingly admitted, "... No. Not certain. But that is only because Celeborn is so hard to pin down. For the life of me I have not been able to figure out just exactly where he came from or how we are related. It is a mystery which eludes me to this day and has caused no end of frustration. And to make matters worse, he refuses to just come out and tell me. I think he finds the whole situation amusing. But to the best of my knowledge, he is my great uncle. If only I could be certain…"
"Cousin!" Elrohir cried excitedly and threw himself into his adar's lap, hugging him tightly.
Meanwhile in Mirkwood
"... Yes, ada? And what else?"
The Elvenking was beginning to sweat sweat slightly under the close scrutiny of wide, cerulean eyes. They were so large, so curious. So probing. He could have sworn they saw straight into his soul. And they kept asking questions.
"Well, um. There was your aduadar, Oropher…"
"Yes, ada. I know."
"And aduamil…"
The tiny blond head nodded.
"And your nanneth, of course…"
"Of course." The elfling agreed serenely. "But I already know of all them, ada. Tell me of someone else."
Thranduil blinked owlishly down at his child. Since when did baby elflings care to hear stories about their family trees. This wasn't normal, was it? Did Thranduil have an abnormal child!? "Um. Well… there was…. you see…" he paused, before brightening slightly. "Well, there is this one elf, Celeborn. I think he might be my cousin."
Celeborn probably doesn't even know how he's related to anybody. He acts all aloof and mysterious and like he's playing us all along, but I bet you he's just as confused as the rest of us and doesn't want to admit it. -Dan