Peter is Clarissa's old suitor from the days of Bourton. He's lives in India, but has come to London to arrange for the married woman he loves (Daisy) to get a divorce
Bilbo took his final stand on Ravenhill among the elves. He also preferred to defend the Elvenking. Bard and Thorin agreed that Thorin would give a portion of his treasure to bard and the Elvenking in exchange for the Arkenstone.
