What is this strange noise my teil is making?

[Niya567765]

She makes the sound when she sits next to her budgie friend at night. This day 2 of her making this sound constantly. And it's only when she's sleepy at night. What does it mean?
listen closely. It sounds like a raspy screech, she does it twice in the vid

 

[Vampiric_Conure]

Hrrrrrmmmm. Hard to tell, but it sounds like content, settling down cockatiel noises to me.

 

[Free as a bird]

Yea I agree, it just sounds like a little cocky settling down. They can make all kinds of cute little sounds