- This article is for the gadget itself.
- For the character, go to Doraemon's Substitute Mom.
Substitute Mother Egg (オフクローのたまご) is a Doraemon's gadget.
Once the button is pressed, a timer will be set, after a few seconds, the egg will shine and "hatch", inside the egg contains an owl-like robot who will register the first living thing she sees as her own child, and will take care of whoever that is for 8 hours exactly like a mother would. After 8 hours the robot will be deactivated.