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On CommCare HQ, go into your desired application. Click on the form in which you are registering your subcase/ related case.
Select the “case management” tab. On the bottom of the case management tab, you will see the heading “Child Cases””. Select the plus (+) sign to open the secondary case you want that is linked to the “main” case. For example, if the child case were a baby, select the module in which the case type is "baby."
If desired, you can add a question that serves as the condition to open the child case (i.e. Only if the answer to <question> is <answer>).
Select the questions/data points that you want to also be associated to the child case. At a minimum you must specify a question that serves as the name of the new case.
Save your changes and try it out!
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Opening Child Cases from a Repeat
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Groups
It is possible to open a child case from questions that are in a repeat group Repeat Groups . This is useful if you want to be able to open multiple child cases of one type - for example if you want to be able to conduct a survey and register a case for every household member.
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Accessing Parent Case Properties
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The application builder gives Child cases the ability to access and update properties of the parent case.
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Note that this only works one-way: the child can access/update its parent case's properties, but the parent case CANNOT access or update properties of its child cases. This one-way relationship can be seen when syncing cases to a device as well. A child case synced to a device will bring the parent with it. A parent case synced to a device does not guarantee that the child cases will also be there.
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