I am using my own light weight MVC framework. I have a main model with two child classes, members\_model and validation model. 

```
Members_Model extends Model
Validation_Model extends Model

```

In the members\_model I need to validate some data. How do I call a validation method from Members Model? Thanks for any help, I have searched and have no solution.

EDIT: TO make it more simple, I need Child A to play with Child B's toy.