Since she hasn’t been sitting on them at night, there is no way they will hatch. There is no development in the egg until at least 48 hours of constant incubation. Since she has never done this, the eggs have not ever started to develop. The eggs must be incubated around the clock for about 3 weeks, so again, there is no way these will hatch since they have been left to cool each night. There are things you should do to discourage this, however, because cockatiels are notorious for becoming chronic egg layers and it is not good for her health. If left unchecked, she will eventually die from the stress to her body.
I wouldn’t let her physically interact with the other bird again. You may even have to keep them in separate rooms or put a visual barrier between the cages. The problem is, a female cockatiel’s hormones can get triggered just from hearing her mate call to her. In the wild, cockatiels mate and lay eggs only one time per year. This is when the days are longer, food is abundant and the weather is warmer. In captivity, we tend to provide these perfect conditions all year. So to try to reduce hormonal behavior, you can begin by limiting her light exposure to 8-10 hours by covering her cage early each evening. If she gets fresh foods, stop offering these for a while. When you do offer any, limit it to once or twice a week. If she is a hand tame pet, limit any petting to her head. Rearrange the toys and perches in her cage and move her cage to a different place in the room every week. Don’t allow her to come and go at will – let her out when you are supervising her and cage her when you aren’t around. Do not give her a nest, tent, hut or anything she can sit in to use as a nest. This goes for the metal tray, also, since she is using it as a nest. Do not give her anything she can shred, like paper or cardboard. Usually doing all of these things can reduce or stop the egg laying. You want to shake up her environment a little bit, and by changing things in her cage and moving it, she will feel like she doesn’t have a stable nesting site. Also, keep the cage in a busy place in the house because breeding bird generally need a lot of privacy.
Thank you for asking Lafeber,