Cockatiel red dropping

Question
Hi there. I have a couple of cockatiels who have very recently had three chicks (three weeks ago). Last night, after cleaning the nest and preparing them for bed I noticed a red dropping on the floor. This morning I have found another one, this time larger (therefore I am guessing it belongs to Poppy the female cockatiel, as she spends the night inside the nest with the chicks). Can you please give me some indication of why she might have red droppings? The droppings look of normal consistency and shape but they are red.
I can not understand this sudden change on colour. Their diet has only changed with the introduction of cooked brown rice (which she eating a lot of), otherwise they both love their vegetables, seeds and millet.They have cuttle fish bone and minerals in the cage as well. Both parents seem perfectly fine, they both eating and drinking plenty and feeding the chicks continuosly.
I would not think they could have injested any objects as they have not toys in this particular cage and they have not been out exercising since the babies arrived. I am taking her to the vet as soon as I identify whether the dropping is hers, but I would also appreciate any information about this subject.
Thanks in advance
Pepa

Answer
Pepa,

Do you have access to an avian vet?  If so, you might want to bring your female cockatiel in.  I'm concerned that an egg may have collapsed in her uterus and that it may be puncturing her, or that she has some other internal injury.  Because it is red, this is fresh blood.  Do you see any red around her vent?

Good luck,

Cindy