### Clue: Character also falling sick after Jack? (4)
### Answer: JILL 
 ### Explanation: Definition: Character also falling sick after Jack
 ILL(sick/unwell) **placed after**(after) J(abbrev. for "Jack", the card in a deck of playing cards).
Defn: Character who came falling/tumbling down the hill after Jack, in the nursery rhyme. And Jill would be sick after falling, especially if she broke her crown as Jack did his.