The child replica geodatabase must be the same geodatabase release as or a later release than the parent replica geodatabase. If you upgrade the parent replica's geodatabase, you also must upgrade the child replica's geodatabase before synchronizing.You can take a look at the following weblink:Replication and geodatabase releases.http://resources.arcgis.com/en/help/main/10.2/index.html#//003n000000z3000000