If you watch the Nick Jr. Presents shorts around 2000 to 2004 such as Dearest's Painting Dreams, Tortillas & Salsa, Seven Days, Six Nights and Babysitting Baby Brother, there is one short that was found. Baby One Afternoon is the only Nick Jr. Presents short that was found. It's about a baby boy who wears a blue diaper staying at home with two dogs such as taking a bath and taking a nap at the end.
The lost short has been found and was uploaded to YouTube by RTXwheels. Skip to 2:23 to see the short.