Cockatiel question urgent?

Yes, they could. Though it is probable that the mom and dad will continue to be a pair, if one of them died, the other would seek a mate. But, even if both are around, the father may still mate with a daughter. The brother and mother could mate if something happened to the father. Or the brother and sister could mate. There is a .07% chance of a birth defect unless they are already inbred. Animals are not people, and do not concern themselves with invented taboos.

However, you can, and should, control the population of cockatiels in your home, as there are human health risks directly attributed to these powder dander birds, especially when kept in in large numbers. Also, it can be hard on the females to be bred too frequently. Try two adjoining cages, one for males one for females. There is not necessarily more work associated with two cages than one. I get a feeling that you would prefer they not inbreed. I would prefer the same if they were mine.

Yes, they could. However, they shouldn't. Inbreeding in birds can cause serious problems in the offspring, unfortunetly I know this from experience (note that not -every- baby will have problems, but there is still a large risk of it happening plus it ruins the blood line).

Cockatiels however usually only have one mate, so the parents are unlikely to pair with their children if they are already together. But make sure the sister doesn't have children with her brothers...

Please do not allow related birds to mate. This is the equivalent to humans having relations to their kin and will only result in unnecessary suffering for the offspring which are likely to suffer birth defects and other inbreeding problems. Please do not allow this to take place. Here is an aritcle for your reference. Best of luck!

http://www.wingedwisdom.com/ww60e.htm

Yes they can mate. But you never ever want to breed two relations together the babys will be deformed and messed up. in some countrys that is elligle. separate them right away!!!

yes they can,they should be seperated.you should breakup offspring and get some new ones in,so they dont start in-breeding.

They can, but do you really want to do that?