Treat indulgently (6)
I believe the answer is:
pamper
'treat indulgently' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for pamper that I've seen before include "baby" , "Overindulge (someone)" , "'Indulge, spoil (6)'" , "Treat with excessive indulgence" , "Spoil, cosset" .)