A:
If the situation is as you mentioned, you do not have to pay Kaffarah for
the boy's death, as you did not do anything wrong. There is no harm in not having him circumcised. It is Mustahab (desirable) to sacrifice a `Aqiqah for him, to apply the Sunnah and seeking its reward. May Allah guide everybody to goodness!May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.