After their coronation, the now King Thranduil and his Queen Êlúriel finally have a moment--the first since Thranduil came home from war and having to bury his father, friends and keeping his promise to become father to his best friend's son. The scene that is most commonly known as “The Conception of Legolas”.
After the fall of Smaug, Ardúin (wife of Elranduil) and Êlúriel tell Thranduil of two messengers from Esgaroth and he learns for the first time where Thorin Oakenshield and his company went after their escape--and the Hobbit that travels with them.
This day, Legolas stands up to his father, Thranduil--asking him for the chance to defend the kingdom against the orcs and spiders.
Thranduil and his mother Queen Nimeithel speak not long after the death of King Oropher. Thranduil learns the truth and the meaning behind his father's words before he died at Dagorlad.
Thranduil's broken heart (original version): Shortly after losing his wife and Queen Êlúriel, Thranduil's sadness, anger and passion collide for a heart-wrenching moment that sets his path to his enigmatic rule forever.
Legolas begins a menagerie against his father's wishes as he's been wandering outside after the curse of Sauron was placed on Mirkwood. The logic of elven children.
Thranduil and Êlúriel meet again not long after her arrival in Eryn Galen. It is also the first time he meets some little elven children that Êlúriel and her cousin Nenloth sit with every day. They are rather precocious little elflings.