Being terminally behind in my reading, I just finished Ariel Levy's profile of Julia Louis-Dreyfus (Dec. 17). I'm afraid I'm obsessing on something that's important to J.L.D.'s life but not so much to the profile. Levy mentions the death of J.L.D.'s "youngest sister, Emma," but she also mentions that J.L.D.'s parents separated when she was one year old, and that her mother remarried. That marriage gave J.L.D. two half sisters, but in further discussion of the family, Emma is not mentioned. I'm guessing Emma was also a half sister, from a remarriage of J.L.D.'s father, since they were both on the board of trustees of her father's art collection.