Puppy Development From 1 to 8 Weeks. Physical Development. At around 12 weeks, puppies gain better control of their bladders and bowels. They may start to sleep through the night without accidents.

In puppy kindergarten, the Duke team followed the development of 101 puppies, tested every two weeks between eight and 20 weeks old. All were Labrador retrievers or Labrador-Golden retriever mixes.

Early dog development has been under-studied, too: It’s over so quickly! There is an increasing amount of work looking at how early exposures can lead to better performance of working dogs.

Puppy development advisor at the charity Chloe Southby said Royal Ascot offered a "unique training opportunity" of being exposed to "extravagant hats and fascinators".