Bird molting, stress or normal?

I have a ateil, she's the second bird I've ever owned so I'm still kind of a novice when it comes to sticky situations. She's about four months old, and the other day the parakeet I kept in a cage next to her died. Since he died she's been pretty upset, kind of pissed off (constantly) and quieter than usual. And now she's started molting. I'm pretty sure she's too young for her first molt, which leads me to think she's molting out of stress from my parakeet dying. I'm not really sure how to handle this kind of molt. I've been giving her millet, spritzing her with water occasionally and gave her some egg, but is there anything else I can do to help her with this situation? I'm planning on getting another atiel to keep her company since she lost her other friend, when's the best time to bring him into the picture?