Model with joined tables

I have a userModel

Code:

[users]
user_id | name | ...

Every user have same avatar images

Code:

[avatars]
avatar_id | user_is | uri | is_dafault | ...

When I got User entity from userModel I wanna access to

PHP Code:

$User->avatars($only_default = false); // return plain array or array of entities of Avatar() 


Yes, I can load avatars directly in method. But what if i need build a table of users with avatars?
I would not like to make 50 requests in a cycle.
How to do it right?
Given that I still need a list of social networks and etc

Maybe something that

PHP Code:

$Users = $userModel->withAvatars()->get([1,2,3]);
$Users = $userModel->withAvatars()->withSocials()->get([1,2,3]); 


Or only this way?

PHP Code:

$Users = $userModel->get(...);
$Avatars = $avatarModel->get(...);
foreach($Avatars AS $Avatar){
   $Users{$Avatar->user_id][] = $Avatar;
} 


(sorry for my english)