Help please.....chicks dying and don't know why

My breeding pair of lovebirds have produced 3 clutches of eggs.. The first clutch produced one baby dead in shell, and the other three eggs were destroyed by the parents...The second clutch produced no babies, and the parents destroyed the eggs...The third clutch produced 6 eggs.. One hatched on Wednesday (2 days ago) and a beautiful chick was present....Within about 3 hours, it was dead, and there was blood in the nest. Yesterday, I noticed another egg had gone, so I gather they destroyed that one...This morning, there was another beautiful chick that had only just hatched, and off I went to work, hoping that all would be OK...I came home from work to find this this chick is also dead, and there has been extensive renovations of the nesting box.....There are three eggs left, and I think two might hatch, and I hold grave concerns about the wellbeing of these chicks....Am desperate for advice on what to do, and why the death of the chicks might have occurred.....PLEASE HELP.....

Unfortunately this is part of the risk when breeding. Not all birds are good parents unfortunately, and you're going to need to remove the eggs and place them in an incubator, and probably end up hand feeding them completely, unless you have a "surrogate" that's able to feed them.

If your birds are young, that could be part of the reason why they're not good parents, but honestly, after the first time I would have intervened. I really wouldn't allow your birds to keep breeding as this is going to keep happening.

Read both of these threads thoroughly because you're making a huge commitment by allowing your birds to continue to breed and hand raising the chicks will be a full time job with plenty of risks because they're so tiny.

http://www.parrotforums.com/breeding-raising-parrots/54987-before-i-start-breed.html

http://www.parrotforums.com/breeding-raising-parrots/54951-time-learn-time-ask.html

Your birds could be too young, in too poor of health, related to one another, inbred themselves, not have what they need in their diet or environment, and they could just be really bad parents. Any of these reasons are enough to raise a huge red flag. Please remove their nest box and prevent them from breeding further.

As for this clutch, do you have the very basic breeding equipment such as brooder, syringes and puppets, formula, coconut water or pedialyte, confection thermometer, gram scale, etc?
And do you know how to use them? If so you need to pull the babies as soon as they hatch and commence hand feeding every hour around the clock. If not, you need to find a breeder in your area who has birds who can act as fosters, or who is willing and has the equipment to take on the new babies.

As for why babies aren't hatching, have you candled them? Do you know how to monitor the progress of a hatch? I hesitate to tell you anything on this, because while I have successfully assisted in hatching birds, doing it wrong is a death sentence. How high is the humidity? How many days old are the eggs? Do you know if they are fertile? If they are still alive?

What are the parents eating? What is the environment like?