The Brownstone Mother hired Ray Stantz and Winston Zeddemore in Ghostbusters II. She led Ray and Winston into room set up for the birthday party. She is to not be confused with the Mother at Birthday Party that dealt with Jason at the same party.
The Brownstone Mother led Ray and Winston into the Brownstone birthday party noting its been a nightmare. She obliged Ray's questions and replied there were 14 children, all about four feet tall. Once Ray and Winston were introduced, she helped out with party items.