Berent, Steriade, Lennertz, and Vaknin (2007) [Berent, I., Steriade, D., Lennertz, T., & Vaknin, V. (2007). "What We Know about What We Have Never Heard: Evidence from Perceptual Illusions". Cognition, 104, 591-630] demonstrate that English speakers' perception of onsets that are unattested in their language mirrors their typological markedness. We suggest that these findings might reflect the presence of universal grammatical constraints, a proposal challenged by Peperkamp's commentary. Our reply exposes mischaracterizations of our claims and presents additional empirical arguments in their support.