@mnguyen
There are several ways to do this in Juji. I believe the simplest way is to change the design of questions to remove the mutually exclusive possibility because such a question allows multiple selections.
#1 One way is to put a yes/no qualifying question first
“Has anyone in your family been diagnosed with digestive conditions?”
Yes, someone in my family has
No, nobody in my family has such a condition
Then as a follow-up to the “yes” answer, ask
“Who in your family has been diagnosed with digestive conditions? Choose all that apply”
#2 The second method is to use one question as shown here
“Has anyone in your family been diagnosed with digestive conditions?”
then add an “Other (please specify)” option. This way will allow users to enter a value that is not included in the list" They may enter “cousins” or “none”
From later data analysis perspective, approach #1 is preferred. From user experience perspective, approach #2 is preferred.
#3 Juji always allows custom topic where special values can be captured.
That would require the use of IDE to customize a topic. Here is how to customize a topic in IDE.