Some of the extras are really peculiar; they're often children of members of the cast, or crew.

Legenda:
  • LoTR: The Lord of The Rings
  • FoTR: The Fellowship of The Ring
  • TTT: The Two Towers
  • RoTK: The Return of The King

Royd Tolkien

Yes, he really is a descendant, specifically he's Tolkien's grand-grandson.
Royd Tolkien
We can find him in RoTK as a ranger of Faramir, at Osgiliath.
Royd Tolkien ad Osgiliath

Hannah Wood

Elija Wood's sister. In TTT she's one of the Rohan women refugee in the caves at Helm's Deep.
Hannah Wood

Calum Gittins and Henry Mortensen

Respectively, son of Philippa Boyens (screenplay writer) and of Viggo Mortensen (Aragorn). In TTT they're two reluctant Rohan children who're preparing for the battle at Helm's Deep. Calum Gittins plays the role of Haifen, son of Hama, the Royal Guard that, when the Fellowship arrives at Meduseld, asks them to drop the weapons before entering the palace, and that will later be killed by wargs along the journey toward the Deep. Callum exchanges also some lines with Aragorn.
Calum Gittins and Henry Mortensen

Sadwyn Brophy

In RoTK, plays Eldarion, the son of Arwen and Aragorn, who Arwen sees in a dream-like vision while she's heading to the Grey Heavens.
He's the son of Jed Brophy, extra in TTT and RoTK variously dressed up as an orc (he's the rider of the warg which then will drag Aragorn down the cliff).
Sadwyn Brophy

Alexandra Astin

Daughter of Sean Astin, plays Elanor, firstborn of Samvise Gamgee and Rosie Cotton, toward the end of RoTK. Alexandra Astin

Maisy McLeod-Riera

Daughter of Sarah McLeod (Rosie Cotton). In RoTK she's Frodo, son of Sam e Rosie Cotton. Maisy McLeod-Riera

Billy and Katie Jackson

Obviously, they couldn't be missing, and indeed they're in all the three movies: the two children of Peter Jackson and Fran Walsh. Hobbit children listening to Bilbo's stories at the birthday party... Billy and Katie Jackson in Hobbiton
... little Rohirrim refugees in the caves at Helm's Deep...
Billy and Katie Jackson at Helm's Deep
... children of Minas Tirith, while they watch in silence the soldiers, Faramir ahead, heading to Osgiliath.
Billy and Katie Jackson in Minas Tirith

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