Wanda Winkle is Bertram's mother who appeared in Throw Momma From the Terrace. She and Bertram haven't talked in years until Jessie set them up and they get along better. She calls Bertram 'Bertrushka' and he calls her 'Mamushka'. She is potrayed by Lainie Kazan.
When Bertram was 10 she made his friend Timmy Schwartz disappear and nobody has seen him since.
She made Bertram's valedictorian speech on "his behalf" but really because she beat him to the podium.