diff --git a/build/CMakeLists.txt b/build/CMakeLists.txt
index 646e8a6e..f7e884f9 100644
--- a/build/CMakeLists.txt
+++ b/build/CMakeLists.txt
@@ -45,6 +45,7 @@ set (LIBI2PD_SRC
   "${CMAKE_SOURCE_DIR}/Base.cpp"
   "${CMAKE_SOURCE_DIR}/util.cpp"
   "${CMAKE_SOURCE_DIR}/Datagram.cpp"
+  "${CMAKE_SOURCE_DIR}/Family.cpp"
   "${CMAKE_SOURCE_DIR}/Signature.cpp"
   "${CMAKE_SOURCE_DIR}/api.cpp"
 )