ses joues ou les joues

Question

I read in the site somewhere that with body parts its always the definite article and not possessive adjective. But here its says ses joues and i think son coeur.

Accepted Answer

Bonjour Radhika,
If you use a definite article in this part of the sentence, it would be written as follows
ce qui donnait aux joues une douce teinte rosée, = which gave to the cheeks a soft pinkish hue,
in which case it seems to refer to "generic cheeks".
In the previous part of the sentence, the use of the pronoun "lui" implies that "visage" belongs to "lui" ; hence, the use of the definite article (as we know whose face it is). In "ce qui donnait...", there's no pronoun used ; hence, the need for the possessive adjective, otherwise it's too ambiguous (and the meaning of the sentence is different).
See the link below:
Special cases when you use mon/ma/mes/etc with parts of the body (French Possessive Adjectives)
I hope this is helpful.
Bonne journée !

Answer

Thank you Céline. for the link too