7 week old Ameraucana Sings!?!?

[HippieHens]

I have a little bearded lady chillin in a cage inside because she was being pecked and we are nursing her back to health. Anyways, she seems very happy and content and makes happy peeps all day. When we leave the room she sings! It sounds exactly like a tea kettle. I have not heard any of my other ladies make this sweet little sound. Have any of you heard this before? What do you think it means? Thanks!!!!