A bird needs a tail knob and stiff tail feathers to wear a diaper.  Young birds
will most likely not have their stiff tail feathers until they are about 4 weeks

These custom reusable garments will allow your bird to have freedom of
movement in your home without the mess. Correctly worn and maintained, the
bird’s feathers will stay clean under most circumstances. The droppings are
channeled away from the bird into a containment pouch to keep the feathers
from getting soiled regardless whether the bird is standing or lying down. The
design allows the bird to preen and access its oil gland and will not interfere
with its everyday activities.  The diaper is adjustable, and is suitable for both
growing and adult birds.

Most diapers are made from a woven cotton-blend fabric. The very small sizes
are made of stretchable fabric. These fabrics are easily washable, quick
drying, and the elastic straps allows for ease of movement and to maximize
comfort. The large diapers have non-stretching straps.  

The diapers are breathable and can be used with or without the disposable
plastic liner. Each order comes with sample liners. Additional liners can be made
at home from easily available materials at pennies per liner. Plastic cups may
also be used for liners after the bird's human becomes familiar with putting the
diaper on the bird. If the diaper is used without the plastic liner, it is
recommended to use a piece of feminine absorbent pad to cover the sides and
bottom of the diaper to form a cup.