Seems like the birds are trying to figure out if our front yard is big enough for the both of them. I have seen quite a few fights between Big Mama and the other female Robin (still trying to name her, any suggestions??). Big Mama always wins. Whenever the other Robin gets to close to Mama's turf, she gets attacked. She tries to put up a bit of a fight but Mama is too big and is more aggressive since she has a nest full of eggs to protect. In the end they seem to work it out. The smaller, younger Robin moves to a distance acceptable to Mama or flies into a tree.
Big Mama seems to be used to me peeking through the window at her. Before she would look startled but now she just kind of stares at me. She is definitely on guard but not willing to fly the nest every time she seems me. It is hard not to watch her throughout the day, but I do try to keep my distance as best as possible. I always approach the window slowly so the sudden movement doesn't scare her away. She does seem a bit more relaxed in her nest than she was the first few days. She used to perk up at every sound and animal that passed by and appeared alarmed. She is still completely aware of what is going on but more relaxed about it now.