Pesters some siblings right away (7)
I believe the answer is:
bothers
'pesters' is the definition.
(I've seen this in another clue)
'some siblings right away' is the wordplay.
'some siblings' becomes 'brothers' (I've seen this before).
'right' becomes 'r' (common abbreviation).
'away' indicates named letters should be taken away.
'brothers' with 'r' removed is 'BOTHERS'.
(Other definitions for bothers that I've seen before include "Troubles" , "Upsets" .)