Babysitter's bane (4)
I believe the answer is:
brat
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">babysitter's bane</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for brat that I've seen before include "Irritating youngster" , "Unpleasant youngster" , "Spoilt child" , "A spoiled badly-behaved child" , "Mervyn -- (Titus Groan)" .)