Question:
Can a Sephardi couple name their child for living Ashkenazi relatives? We would ask permission but wondering if there is any halachic reason not to?
Answer:
This is a matter of custom. The Sefardim feel that it is an honor to name a child after a grandparent, and it is considered a great honor, that the persons sees his continuation even while he is still alive. The Ashkenazim however feel that this is something reserved for the deceased, and doing so is usually taken negatively. It is not for a specific halachic consideration, therefore if the relative consents to it, it is permitted.
Best wishes
Sources:
Poskim
