Zebra mother plucking father and fledglings

Question
Thanks for your question forum I have a scenario I have not quite seen addressed any where I look on the Internet.  I have two female and two male zebra finches I bought in mid-December.  They share(d) a 23x18x29" high cage. One pair laid eggs in a parrot cup (I read they liked to sleep in nests, so all four could fit in, lined with timothy hay).  Instead, one pair laid three eggs.  The female, after laying, BADLY plucked the male.  I know this happens but this was extreme.  No blood, but viewed from the top, he has no feathers (I am talking completely bald, like a chicken carcass)from his head crown and back to tail end, just feathers on his wing ends, some on his belly, longest tail feathers and his cheeks.  The first few days I thought he was going to die, that is how bad he looked.  You can even see the skin where the wings grow from his body. He looks a tiny bit better now and has fine energy/appetite. The two fledges must be 3 weeks or so, can fly, but I have not seen them eat on their own.  Today, i noticed mother plucking feathers from her fledges, feathers missing from the wing/body spot to the back of the babies'necks.  I separated the fledges and male (and their parrot nest cup)from the female into a 30" cage.  Will the male continue to feed the babies?  Should i add the female to the cage to insure the babies are fed?  Should i just put the male and babies back in the original cage?  My other pair of Zebras are completely fine, even gorgeous! I guess my primary concern is I am worried about the babies as the mother was so aggressive to the father, will she pluck the babies to death? Thank you so much for any timely help you can offer!

Answer
First of all, I'm glad to hear that you did research on what your birds like. Not a lot of people will read up on the animals. So kudos on that; it makes me happy.
Secondly, there are a number of reasons the female could be picking at the feathers. The most likely one is nerves. I'm assuming that she is a first time mother. This MAY get better as she gets older but I wouldn't rely on it. You can buy some spray that discourages picking and see if that makes it better but I would wait until the babies are weaned and his feathers have grown back. This sometimes work but it is not 100%. You can also buy them both new mates and see if that helps. You can get them both new mates if you like (chances are that the new male won't tolerate picking) but she can never have babies or this will repeat itself.
For now it is best to leave the father and babies alone. He will more than likely continue to feed them but it is best that you keep an eye on the babies and take up hand feeding them (VERY dangerous with fledglings as they can regurgitate the food and suffocate) if necessary. The website provided offers seeds that are excellent for fledglings just learning how to eat. If you like, I can also give you a recipe for "Eggfood Mix". It is highly nutritious (and fattening so be careful)and birds learn to adore it quite quickly. Eggfood Mix is also an excellent way to help babies learning how to eat because the food is soft and there are no shells for them to get rid of.

Just a side note, when your females are laying, it is a good idea to increase the calcium they get to prevent "wind eggs". Wind eggs are when the egg inside the female had very little shell or no shell at all. Wind eggs are extremely difficult to pass and often kill the female. The website provided also carries supplements you add to the water. I also use iodine to aid them with their feather growth. (You don't want to give water supplements everyday to your birds. I usually go one day calcium, one day iodine, and two days regular)