3mth old son just recevied a heart transplant because his old heart was not developed properly. My question is: He has a non-muslim heart beating inside of him, is it ok? Or did we make a wrong decision to have had the transplant?

Praise be to Allaah.

We put the following question to Shaykh ‘Abd-Allaah
ibn Jibreen:

Is there any objection (in sharee’ah) to transplanting the heart
of a dead kaafir into a Muslim body?

He, may Allaah preserve him, answered as follows:

No, because this organ is not the seat of disbelief or faith.