I've always been told that when naming a newborn Jewish child, it was improper to give him/her the same name as a living relative. What is the root of this tradition, and is using the first initial of a living relative's name also frowned upon?

The second time, it appears here, in this form: I know that it is not law, but custom, regarding Ashkenazim not naming babies after living relatives. However, I am very torn as I am about to have my 3rd (and last!) child. We have named our other 2 children's (English) middle names after deceased relatives. My grandmother is 85 and not doing well but we don't expect her to pass away anytime in the immediate future. I am her only grandchild and I would really like to honor her by naming our upcoming baby with her name as our baby's middle name; however I do not want to be doing something horribly wrong in other's eyes. Of course I do not wish my grandmother would die but the reality is she will at some point in the near future given her age while my child will likely live a long life and I think honoring my grandmother with her name as my child's middle name would be a special way to honor her. What do you think? My husband is fine with it but my in-laws are not sure. I am a convert (Conservative) so my family doesn't really have much input (however my grandmother is Jewish). Thank you!

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