Nori, Ori and Dori
As played by Mark Hadlow, Jed Brophy and Adam Brown.
It seems rhyming was a mandatory convention when it came to naming dwarf siblings. Dori is the strongest of the Company of Dwarves and is described in the novel as "a decent fellow, despite his grumbling." Mark Hadlow plays his eldest brother and was cast having previously worked with Peter Jackson in Meet the Feebles and King Kong.
All three brothers are capable flutists and Ori is one of the dwarves who accompanied Balin to Moria. He recalls his last moments in The Book of Mazarbul, which Gandalf reads from as the Fellowship passes through Balin's tomb.