Bird feathers are very delicate and the natural oils on humans hands can strip them of their weatherproofing. Avoid handling and wear gloves.
When baby songbirds are ready to leave the nest, or fledge, they will have most of their adult feather cover and little bits of fluffy down sticking out in between. They can’t quite fly yet, so they will spend up to a week or more on the ground strengthening those flight muscles while the parents continue to care for and watch over them. This is a normal and crucial stage in development and so important that these babies are left alone to develop properly. Keep pets and children away until these fledglings can fly away on their own.
Fledglings in a dangerous area should not be moved more than 6 metres/20 feet or the parents will not be able to find and support them.