Youngest in family's the one after the others to give parents a break (7)
I believe the answer is:
babysit
'break' is the definition.
The answer and definition can be both to do with social activities as well as being verbs in their base form.
Perhaps you can see an association between them that I don't see?
I can't explain the rest of the clue.
Can you help me to learn more?
(Other definitions for babysit that I've seen before include "Look after children temporarily" , "Supervise in loco parentis" , "Mind" , "Take charge to allow parents to go out" , "Tend to kid" .)