In the original Jacob Two-Two Meets the Hooded Fang (1978), the character of Shapiro had the alter ego of Emma and was played by Marfa Richler. In the 1999 version, Shapiro's alter ego is actually named Marfa (played by Alison Pill this time around).
The book for which this movie was based was written by Mordecai Richler, who based the characters of Jacob and his family off Mordecai's own youngest son Jacob, and their family, with each of the children's names based off his real children: Daniel (eldest), Martha/Marfa (second eldest), Emma and Noah (Twins, 2nd youngest), and of course Jacob (youngest).