Budgie is sick that I bought yesterday. What should I do?

[minka]

Hello I am new to this forum and new to owning Budgies. I already made one mistake and that is buying my two budgies from Petco. I know it's terrible but I was previously uninformed. So my first Budgie was bought 3 days ago and she is doing very well. She is eating, singing and sometimes will eat millets from my hand. I was then told by a friend  in order for my Budgie to be truly happy I should purchase a second one, an albino budgie, and brought her home. They instantly bonded and started preening. Today I went to check on them and the albino has green poo all over her feathers by her vent. A sure sign of diarrhea. Now I am at a crossroads. Do I return the sick budgie? Or should I wash her and keep her separate for a few days to see if it is just stress related? 

[helenmat]

To be honest even if you do now separate them it really is too late to prevent one from passing nasties on to the other. The second bird should have been quarantined for 4 weeks before introducing to the first. Did your second bird come from the same store and cage as the first? Runny poop can definitely be stress related. If you think you can clean it off without creating more stress then go ahead. Does the second bird seem well otherwise?