Caleb's Crest part is an item obtained during Family Crest. Each part of the crest is owned by one of three Fitzharmon brothers, who have all left their family home. Each brother took a separate piece of the crest with him to prevent the other two brothers from inheriting the family fortune.
Each brother requires a certain task to be completed before he will give up his third of the crest. Caleb requests cooked shrimp, salmon, tuna, bass, and swordfish.
The three pieces should be combined to make the whole family crest, which can then be given back to Dimintheis Fitzharmon, the boys' father, in Varrock.