I have a ssis project in which the master package contains many child packages. All the child package are invoked with execute package task. I need to pass the "begin date" value from master to all the child package. I know we have parameter binding option in which we can pass the variable value, It works only for project reference. But the problem here is that all the child packages have reference type as "External reference". So the parameter binding is disabled. Is there is any way we could pass the value from parent to child for reference type : "External reference". 
I'm using SQL server 2014 Datatools.

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