SOLVED. Middle Grade or YA fantasy: not first book in series. Travelling group wearing animals masks that adhere to their faces. [s]

[April]

Group of young people on a quest come across travelling performers wearing masks. The male protagonist reminds woman leader of her son. They stay with them a while. When one of the trope members is murdered girl tries to remove his mask only to discover it is permanently stuck to his face. At the same time the male protagonist is talking with the female group leader and she asks him to try on her son's mask (a bird because he was a singer) in an attempt to trap him with the group. Girl saves him in time.
Later in the book they are captured and find the woman's son being treated as a pet by their captor for his singing. He writes a song with a secret message in it. On the page is a drawing of birds flying from a cage, when the heroes eliminate all the mentions of birds in the poem it reveals the message that he is a prisoner and needs help.
Please help me! I remember all these details yet cannot find it and never read any other books in the series

[Rainbowheart]

When did you read it?

[April]

I read it back in 2006ish

[Rainbowheart]

The Keeper's Shadow?

[Becca]

Shadowgate by Emily Rodda, from the Deltora Quest series?

Then it struck him. The bird mask he was wearing must have once belonged to Bede. When Bess looked at him, she saw her son reborn.

Taken together, the last words of every line of Bede's song formed a message.
Kristen is evil. I am her prisoner.

[April]

That’s it! Amazing.

[Kris]

Glad you found your book, April.

Shadowgate (book 2) of the Dragons of Deltora series by Emily Rodda - Becca's find.