YA Fantasy with possible Russian roots. Two children, a boy and girl, who may have magical powers? On a boat going somewhere at the beginning of the book.

[Bridgett]

I've been trying all day to remember a book that I started reading between four and seven years ago. I am pretty sure it is a YA Fantasy and I think it may have been part of a series and may have had influence from Russian folklore but I'm not 100% on that. I remember the book beginning with two children or teenagers who have powers going somewhere on a boat. I know that there is a voyage by boat somewhere in the beginning of the book. That is all I can remember!! I hope someone can help.

[Sarah]

Based on this description, the only thing that comes to mind is Doll Bones by Holly Black: https://www.goodreads.com/book/show/1...
The kids in this book travel by boat for some time.

[Blue]

Shadow and Bone

They don't start on the boat but there is a boat a few chapters in and they start as children and then teens.