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Rivendell:
"He was not of Rivendell, Elrond," said Glorfindel.
"We already knew that, Glorfindel!" said Elrond, trying not to let his exasperation get the best of him. First Glorfindel had decided that someone had to go to see the dead body, out of formalities, even if there were only a handful of blondes in all of Rivendell. Then he had decided that he should be the one to go since he knew almost all of Rivendell. After taking much longer than he should have, Glorfindel finally came back to Rivendell and spent half an hour on a report that shouldn't have taken more than fifteen minutes! If Elrond didn't know better, he would have said that Glorfindel was trying to irritate him.
"Of course, but formalities must be observed," said Glorfindel.
Elrond's eyes narrowed, now he was sure Glorfindel was provoking him. Glorfindel never observed protocol if he could avoid it. He returned to his papers, "If that is all, Glorfindel…"
"By the way, Elrond, the man looked like an older Legolas. Could they be related in any way?"
Elrond's head snapped up, "Legolas?"
"Yes, the unknown elf, he looked like Legolas. Nearly a mirror image. From a distance, he could pass as him unless you know them well. Rather like Elrohir and Elladan," that said, Glorfindel turned and opened the door to leave.
Elrond thought for a moment a gestured to a chair, "Sit back down, Glorfindel."
He waited while Glorfindel complied before saying, "We, that is, Gellyth and I have been talking. It has been long enough ago that I barely remember the man, but does Thranduil look like Legolas at all to you?"
Glorfindel thought for a while, "Now that you mention it, he does, rather. I didn't notice before because Legolas was so jumpy, but you're right, he would be nearly a mirror image if Legolas was taller and prouder."
"Yes, we thought so as well. But if Legolas is indeed Thranduil's son, that means his mother, possibly his father as well, were captured by slavers," said Elrond.
"I would say it is probable that Thranduil was either killed or sold with his wife. After all, Thranduil was so in love with Eledwen. I do not believe he would have left her for the world," said Glorfindel.
"Yes, your right. However, Thranduil only had two living relatives, one of whom was his mother and she faded a few years after his disappearance. The other was a distant cousin, Baelor, who currently sits on the throne. He was the last to see Thranduil before he disappeared. If Legolas is Thranduil's son, not only is the throne of Mirkwood his by right, that dead elf must be Thranduil," said Elrond.
"Nay, that elf did not look Thranduil's age. He looked closer to two thousand. There were whispers in Mirkwood that he could have, perhaps, been the missing heir trying to return to Mirkwood. Others say that it could not possibly be, he is much too old. On the other hand, death changes one's countenance, it can make it younger than the person was," said Glorfindel.
"Hmmm… yes. As soon as Legolas recovers, mind and body, I shall speak to Galadriel, she might know better than us, having closer ties to Mirkwood," said Elrond.
"Is that wise? Legolas might be happier if he is unaware of being the crown prince and only true heir to the throne of Mirkwood. Besides, no one knows what happened that night. Only Thranduil, Eledwen, and Baelor know. Perhaps the cousin forced Thranduil to leave. If that's true, revealing Legolas' possible parentage could place him in danger," Glorfindel cautioned.
"He is bound to find out. Better he can still trust us because we told him then he finds out on his own and learns we knew but didn't tell him. Besides, it's not as though we are announcing it to all the elves of Middle Earth, we are just telling him, he does not need to tell anyone if he does not wish to," said Elrond.