I not long ago undertook to say Kaddish for the full year for a cousin of mine who died childless. I also have undertaken (for many years already) to say Kaddish for grandparents and an uncle who also has no one to say Kaddish for them on their Yahrzeit. So this year I have a problem when these clash, like next Shabbes it is my late grandmother’s Yahrzeit and I have the daily obligation I undertook on behalf of my cousin. Obviously on my late parents Yahrzeit where I am a Chiyuv on all acccounts I get someone else to say Kaddish for my cousin. What is the correct thing to do in the case of a clash like I have coming up next Shabbes?
Shalom, Thank you for your question. You seem to be under the impression that each departed soul needs a separate person to say kaddish for them. But this is not the case – one person may say kaddish for multiple souls at the same time. In fact, it is quite common to have someone who is already saying kaddish to "take on" additional souls in their kaddish. They do this by having intent for the souls of all those they want to "cover" with their kaddish. So, in your case – it is a great mitzvah that you are doing to make sure that kaddish is said for all these people. On the days when you have more than one obligation, you should intend your kaddish for all the particular souls, as well as the general intent of kaddish which is to glorify Hashem's name in the world. Blessings.