Introduction of new budgies

Question
Hi... new guy here..I have a cage 15" x 36" and have two birds with babies and shes laying eggs again.. my question... can I introduce another pair to this cage,with a breeding box, shes ready for breeding,without affecting the breeding of the first pair.

Answer
Hi there,
I wouldn't put them together just yet.  Moving into a new cage is stressful for birds.  It could put unnecessary stress on the parents and the new pair.  Keep in mind also that the parents will do anything to protect their offspring.  They may attack the new pair if they see them as a threat to their eggs.  I would wait until the babies are four-six weeks old before putting them together.
Good luck!
-Leah