Symbols: children carrying them briefly (6)
I believe the answer is:
totems
'symbols' is the definition.
(I've seen this in another clue)
'children carrying them briefly' is the wordplay.
'children' becomes 'tots' (tot is a kind of child).
'carrying' is an insertion indicator.
'them briefly' becomes 'em' (abbreviation; 'briefly' asks for a short form).
'tots' placed around 'em' is 'TOTEMS'.
(Other definitions for totems that I've seen before include "Natural objects adopted as emblems" , "Motets (anag.)" , "Revered objects" , "Emblems once adopted by native Americans, seen on pole" , "Signs" .)