It appears to me that one of the baby Doves is not developing proplerly. My first instinct is to scoop him up, bring him into my home and try to raise him. However, I know this is not feasible or wise. I am also a believer in letting nature take its course. I have to assume there is something wrong with him and nature is weeding out the weak. It is sad to see him so small and unfeathered compared to his sibling.