She possibly has within her a warm heart (5)
I believe the answer is:
sarah
'she' is the definition.
'within her a warm heart' is the wordplay.
'within' means one lot of letters goes inside another.
'her' becomes 'sah' (I can't justify this - if you can you should believe this answer much more).
'heart' means to look at the middle letters.
The middle of 'warm' is 'ar'.
'sah' enclosing 'ar' is 'SARAH'.
'possibly has' acts as a link.
This may not be correct. Some or all of it may belong to another bit of the clue.
Can you help me to learn more?
(Other definitions for sarah that I've seen before include "Girl" , "Abraham's wife in the Old Testament" , "Woman" , "Abraham's wife (OT)" , "- Bernhardt, Fr. actress" .)