Call, another model in a model

[eluser]Colin Williams[/eluser]
Use the get_instance() function to get an instance of the CI superobject, then use the normal APIs to load and call model functions.

Code:

$ci =& get_instance();
$ci->load->model('other_model');
$ci->other_model->get_related(3);

Another thing, is it possible to pass a parameter to Model (or Library) constructor?

It wouldn't make much sense to, since models in CI are not really designed to represent single objects (they are purely organizational).