Baby finch molting

Question
QUESTION: My 5 baby finches left the nest last week. One is slightly larger than the others and has lost feathers on its back and is bald there. Is this normal timing and structure of first molt, or is there something wrong?  Sorry, the attach image is greyed out, so I can't send picture.

ANSWER: It sounds like the parents are plucking at them. Watch the cage closely and see who is going it and remove them

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QUESTION: Thank you for your response. I haven't observed plucking, but it may have happened in the nest. The baby spends more time than the others on the cage floor but is still lively.  It almost seems like the lack of feathers makes flight difficult.  Is it too soon to isolate that baby, is it still learning life skills from parents and siblings?

Answer
It's still too soon for the baby to be separated. I would continue to put the baby either back in the nest or on an upper perch. I doubt the missing tail feathers are causing the flight trouble. Fledglings just aren't that coordinated. If you're really worried, put a couple more perches in. Other than that, keep an eye on the baby's weight and make sure he's still getting fed.