Fortunately they are in quite a big cage and the box doesn't take up too much space. So far the budgies are only using it to poop on and they chewed the bamboo on the roof.
Meet Roxie the budgie (blue) and Elvis the show budgie (green). They love each other very much and are forever busy kissing or preening each other.
I had to take the budgies to the vet a while ago and Andrew went with me. He asked the vet a lot of questions. One of the questions was whether the budgies would mate. The vet replied that it is possible, but that budgies are very silly and lay their eggs just anywhere!
We will have to see what happens!