Charlie's baby

Charlie- the male blackbird that lives in my back garden has had chicks. There are two and this is his second brood this year. I know it is not great quality but hey it is recognisable. Blackbird chicks leave the nest before they are able to fly. I would have thought this is not a great strategy for survival. They are fluttering about the yard and hiding in the undergrowth. According to the internet ( the font of all knowledge) they will be able to fly in about 4 or 5 days and will be independent in about 3 weeks.