Board Thread:Spoilers!/@comment-1916997-20180101222954/@comment-25926288-20180324224511

It's obviously not Jace because where she was.

Andrea died while Jace and Sabine were watching Lucy, Sabine went to go get Andrea.

Nick was there in the Hospital (as you can see in some background shots and obviously got his blood tested. Nick killed Andrea, if it's someone that related to the Ella-Henry-Lucy gang.