Yes, Doraemon's mother does exist, and she is...
You heard that right! Despite being a futuristic robotic cat living with the Nobi family, Doraemon indeed has a mother. More accurately, this mother figure is a comically touching yet equally poignant 'accident'.
Doraemon's mother character appears in the episode Doraemon Also Wants a Mother. In reality, this mother figure makes a very serendipitous appearance, disguised as... an item in Doraemon's pocket.
In this episode, Nobita disobeys his mother, leading to Doraemon's annoyance. The robotic cat then retrieves a gadget called the Substitute Mother to 'teach a lesson' to the mischievous boy. This gadget identifies the first person it sees as its child, and Doraemon falls victim to Nobita's deceit.
Thus, Doraemon ends up with an involuntary mother. Doraemon's mother has a tall stature, resembling a mix between a bird and a cat, with pink fur. This gadget embodies all the traits of a mother, being affectionate yet stern, disapproving of mischief. Initially, Doraemon resents his mother because, after all, he is still a robot cat manufactured in a factory.
However, afterward, Doraemon was deeply touched by the maternal love of the gadget. This 'mother' figure made donuts for Doraemon to eat, and despite their less-than-stellar taste, Doraemon enjoyed them nonetheless. Sadly, this 'mother' figure was just a gadget and couldn't stay with Doraemon forever. The tearful farewell between the 'mother' and 'child' left viewers profoundly moved.
That's the surprising identity of Doraemon's unexpected 'mother'. While this maternal bond was short-lived, Doraemon still has the Nobis, with Nobita and his family loving him unconditionally. Additionally, Doraemon still has his little sister, Dorami, who always supports him whenever he needs it.
Image: Nippon TV