In my use case, I want to extract the value 'male' in the entity gender and the value 'adult' in the entity age-group from the single word 'husband', or likewise, I want to extract the value 'female' in the entity gender and the value 'senior' in the entity age-group from the word 'grandmother'.
There are two problems that you will run into when trying to implement this in Dialogflow.
1: Dialogflow cannot extract multiple entities based on a single value. Even if you add a phrase twice with a different parameter it will only return one of the two entities.
2: Dialogflow cannot set entities based on the value of a different entity. If you wish to use something like this, you will need some code that does the setting of gender and age-group for you.
So you could create an entity and add husband, wife, grandfather and grandmother as values and then check this entity in your code and set variables in your code to male, senior etc.
The closest you can get without using any code would be by expanding to two entities in the parameters, this way you can add husband as a synonym for both entities:
For this example I've used the following entities:
Due to the synonym's Dialogflow will now change husband to a value of male when you expect an entity of Gender. The same trick has been used on the age-group entity for adult.
Finally, I've used the below intent setup to create the example: