Question:
What if someone missed saying Kaddish?
Answer:
If someone missed saying kaddish it is still possible to say kaddish at another minyan. If there isn’t any other minyan, I don’t know of any sources that talk about a way to make it up. There are however other things that one can do l’iluy lishama, such as learning mishnayos, or giving tzedakah, while it doesn’t makeup the kaddish, it is still giving to the neshoma, in a different way.
