docs: variant dependencies (#6758)

website/docs/reference/dependent-features.md

@@ -5,17 +5,34 @@ title: Dependent Features
 :::info Availability
 
 **Dependent features** were first introduced in Unleash 5.7 for Pro and Enterprise users.
+
+**Variant dependencies** were first introduced in Unleash 5.12 for Pro and Enterprise users.
 :::
 
 ## Overview
 
 Dependent features allow to define a child feature flag that depends on a parent feature flag.  
-A feature flag can have only one parent dependency but multiple child flags can share the same parent. For a child flag to be activated, its parent dependency must be enabled.
+A feature flag can have only one parent dependency but multiple child flags can share the same parent. For a child flag to be activated, its parent dependency must be satisfied.
 
 ## Parent dependency criteria
 
 * **Project Association**: Both parent and child flags should belong to the same project.
 * **Single Level Dependency**: The parent flag can’t have its own parent, ensuring a straightforward, single-level dependency.
+* **Parent Value**: Parent value should match predefined feature status and variant criteria.
+
+### Parent value criteria 
+
+In order for the child feature to be evaluated, the corresponding parent value criteria must be satisfied.
+
+Parent value criteria can be set to one of the 3 options:
+* parent feature must be **enabled**. 
+* parent feature must be **disabled**. This is useful when your parent is a [kill-switch](./feature-toggle-types.md#feature-toggle-types) with the inverted enabled/disabled logic.
+* parent feature must be **enabled with variants**. This is useful when your parent is part of A/B testing, and you need **variant dependencies**.
+
+For the **variant dependencies**, if the parent feature variant is evaluated to the expected value, the dependency is satisfied.
+You can specify variant values from all [strategy variants](./strategy-variants.md) and all [feature environment variants](./feature-toggle-variants.md). The parent dependency variant 
+is compared to the actual value that the parent dependency is evaluated to in a given environment.
+Consult [strategy variants order](./strategy-variants.md#strategy-variants-and-strategies-order) and [variants comparison](./strategy-variants#strategy-variants-vs-feature-toggle-variants) sections for more details on the variant evaluation order.
 
 ## Managing dependencies