Some Shakespearean scholars speculate on the relationship between Hamnet and his father 's later play Hamlet , as well as on possible connections between Hamnet 's death and the writing of King John , Romeo and Juliet , Julius Caesar , and Twelfth Night .
Other ideas state there is a relationship between Hamnet 's death and the writing of King John , Romeo and Juliet , Julius Caesar , and Twelfth Night .