MADISON, Wis. (WTAQ) - Friday is the second anniversary of the murder of former UW-Madison student Brittany Zimmermann in her off-campus apartment and Madison Police are still looking for her killer. Investigators and Zimmermann’s family believe someone knows who did it, and that has brought a renewed plea by her parents for donations to a reward fund. There’s still a $15,000 reward for information leading to an arrest in the Zimmermann case.