# Using parent information with Aurelia Validation

**URL:** <https://discourse.aurelia.io/t/using-parent-information-with-aurelia-validation/2368>\
**Category:** Help Requests\
**Created:** [March 13, 2019, 2:50pm UTC](https://discourse.aurelia.io/t/using-parent-information-with-aurelia-validation/2368 "2019-03-13T14:50:34Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![SNO](https://yyz1.discourse-cdn.com/flex027/user_avatar/discourse.aurelia.io/sno/32/650_2.png) [@SNO](https://discourse.aurelia.io/u/SNO)\
**Post date:** [March 13, 2019, 2:50pm UTC](https://discourse.aurelia.io/t/using-parent-information-with-aurelia-validation/2368/1 "2019-03-13T14:50:34Z")

</div>

Hello all,

I’m not sure if this question has already been handled in this blog but I couldn’t find anything. Currently my problem is the following:

I have two models, a parent and a child:

```auto
export class parent{
    public property: boolean;
    public childs : Child[];
}
export class child{
    public childProperty: boolean;
}

```

Now I want to add a validation rule to `childProperty` that it has to be true if the parent `property` is false. How can I handle that?

```auto
ValidationRules
    .ensure((c : Child) : c.childProperty)
    .satisfies(
          ///IF PARENT "PROPERTY " is false && childProperty == true) return false ??
    )
    .on(child)

```

I know I could validate the “childProperty” starting on parent, but the aim is that the “childProperty” input field is marked red if this rule is not valid.