Lovebirds eating babies?

Question
Our birds are in a large double cage with a nesting box.  The male is 8 years old, having a mate that died last year.  The female is 7 months old.  They seem to get along well.  The room is a little dark and cool now that cold weather has set in.  Could that cause a problem?  There wasn't any blood that we could see in the nesting box or on the birds.  The baby just disappeared over night.  We can only assume the first egg hatched without our knowledge and the parents did something to that baby too.  I don't want to have to hand-raise the babies straight from hatching.  I was planning to wait until they were a couple weeks old.  Thanks for your help.

Lori
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-----Question-----
Our love bird pair laid four eggs and have been sitting on them religiously.  We saw that there was a newly hatched baby last night, and only two eggs left.  We wondered about the fourth egg.  This morning there is no sign of the baby, and only the two eggs.  Have the lovebirds been eating their babies?  Why would they do that after taking such good care of the eggs.  We don't check on them more than once a day, so I don't think they are over-stressed.  What can we do?

Thanks.
-----Answer-----
Hi, Lori.  Thanks for posting.

Parent birds don't usually eat their eggs/babies unless they feel they are in some kind of danger.  Are your lovebirds housed with any other birds or are there any other birds close by?  Do you have any other animals that have access to the birds?  Have you seen any blood or other on the adults' beaks or in the nesting box (I'm assuming there was a nesting box), cage bottom, etc., i.e., any evidence of egg shell or babies?  How old are your lovebirds?  I need as many details as you can provide in order to try and figure this out.

Thanks.    

Chrys

Answer
Lori,

The room the birds are in should be lit...parrots need full spectrum lighting for about 4 hours per day, then normal lighting the rest of the day.  The room should be warm enough so the birds don't get sick...how cool are you referring to?

These things shouldn't be a factor for the parents and their babies, but if the birds feel there's some type of threat present to their babies as a result of a dark, cool room, then it's possible I suppose.  You'd know more about this than I, since you know your bird's behavior better than anyone else does (does a dark, cool room affect your lovebirds when babies/eggs aren't present?).

Have any changes been made in the room where the birds are kept (furniture, new colors, new people in the house, familiar face no longer in the house, diet changes for the birds, are they near a window where they can see outside, etc.)?

Chrys