DRAMATIS PERSONAE
KING HENRY IV
PRINCE HAL – later King Henry V
PRINCE JOHN OF LANCASTER – Henry's son
DUKE OF GLOUCESTER – Henry's son
DUKE OF CLARENCE – Henry's son
EARL OF WARWICK
EARL OF SURREY
Humphrey, Duke of Gloucester was the youngest son of  Henry IV.  He has a small part in  2 Henry IV 

Henry IV Part 2 Characters of the Play