Goliath
Goliath is described in the biblical Book of Samuel as a Philistine giant defeated by the young David in single combat. The story signified Saul's unfitness to rule, as Saul himself should have fought for the Kingdom of Israel.
Nathan (son of David)
There are also instances in the Hebrew Bible where the name Nathan is mentioned, but it is unknown whether it is referring to Nathan the prophet or Nathan the son of David. One instance of this appears in the first book of the Book of Kings. In 1 Kings 4:5 it states
"Azariah son of Nathan—in charge of the district governors;" when listing the chief officials of Israel under the reign of Solomon. The passage does not specify if it is the son of Nathan the prophet or Nathan the son of David.