Very cute!!
I believe it was perhaps the family of House wrens which killed my old, large Lc Irene Finney look-alike 2 Summers ago. I had then split the basket of that one and placed a large chunk into a new wire basket. House wrens are small enough to fly through the cage, but normally I am fine with that. Unfortunately they decided to tunnel into the basket/ medium and raise a family in there. ( Screaming at me every time I entered the cage....
) At the time I found the behavior of those birds simply amusing and left them alone. I always wondered if that nest (and killing most roots along with that) was the reason the plant took a straight nose dive.