Jack Bratman, a resident of Fieldston, welcomed a grandson, Max Liron Bratman on Jan. 12.
Max's parents, Jordan Bratman and pop icon Christina Aguilera, say he weighed in at six pounds, two ounces when he was born at Cedars-Sinai Medical Center in Los Angeles, Calif. He was 20.5 inches tall.
Liron means song in Hebrew and Ms. Aguilera, a singer and songwriter, laughingly told friends that her son's name refers to the fact that he is her greatest composition.
She took the unusual step of celebrating Max's birth by releasing a downloadable music video on her Web site of her song, "Save Me From Myself," which features footage of her wedding day with Mr. Bratman, who grew up in Riverdale.
A message on the site told her fans it was, "Just a little something to say 'thank you' for your undying love and support."