Parent lovebirds rejecting babies?

[Jewelr]

My family recently bought a breeding pair of lovebirds, which have now laid and hatched eggs. The first egg hatched on 1/19 and the second not long after and those two chicks appear to be gaining weight and are healthy. They are now bigger than the other two that hatched, of which neither survived longer than a day.
Today I discovered the second new chick and we decided to go ahead and try and feed it to keep it alive but by the time we decided it was already passed ):
there is one more egg we plan to hand feed if it hatches but my question is why they are rejecting the new babies and can we prevent? Is it the size difference? We plan to keep this pair and have a lot to learn so any information would be helpful. We have not bred birds before so this is all new to us.

 

[ParrotNuts]

@PoukieBear

 

[Shezbug]

@Zara

 

[Zara]

my question is why they are rejecting the new babies and can we prevent? Is it the size difference?

Sometimes it just happens. It can be for many reasons, like inexperienced breeder pair, too many chicks, not enough food available to the breeder pair, absence of male.
The size of the first chicks won't help, they will be first in line for feeds and if your parents don't keep up the littlest ones miss out.

 

[Jewelr]

Sometimes it just happens. It can be for many reasons, like inexperienced breeder pair, too many chicks, not enough food available to the breeder pair, absence of male.
The size of the first chicks won't help, they will be first in line for feeds and if your parents don't keep up the littlest ones miss out.

Thank you, the last one hatched today we are going to go ahead and hand raise this one. We know it will be hard work but I don’t want to let the little baby get neglected ):

 

[Zara]

If the parents aren´t attacking it, you can try to co parent.
Parents brood all the chicks, you check in and supplement feed the ones who aren´t getting fed. If the parents will allow it, it is much easier.

 

[tka]

If you absolutely have to remove chicks from the nest to handraise, take the older ones. They're bigger and have already had some parental care. Newly hatched chicks are very fragile. In addition, there's some evidence that the food that the parents provide contains important bacteria and other flora that helps establish the chick's own digestive system.