CHANGELOG.md in astrolabe-1.2.1 vs CHANGELOG.md in astrolabe-1.3.0

@@ -1,8 +1,12 @@
 # Changelog
 
 ## Development
 
+## v1.3.0
+
+* Add `Node#sibling_index`.
+
 ## v1.2.1
 
 * Re-release 1.2.0 due to an error in `rubygems.org`.
 
 ## v1.2.0