My son had our 21 day old Conure on Our Bed and I told him to keep the little bugger under the drop sheet I had on the bed. So my son lets him venture off to the end of the drop sheet and this little bugger lets it go all over our bed!! I'm telling my son off while trying to get something to wipe it off, he's laughing and my wife is telling me off!!
Even though the baby conures are small, their droppings are 100% full size now
Yes birds are great like that.
BTW: to clean the grate on our cages, I hose it down and give it a light brush while cleaning the rest of the cage and then I go back and repeat the process every now and then while cleaning the rest of the cage. This softens up the dropping and take a layer off each time you brush.