Laravel join and relation for membership and it's child

well, I have these three tables -

membership, plans, stocks, and stocks_with_plan - this is I am using for they have multiple stocks with a single plan

so now I am using the model to get the data off it

but I am not getting the right way to get the correct way to get the data I am getting his in dd

Membership Relation - Plans

now I want the stocks_with_plan under the plans relationship and stocks table under the stocks_with_plan

stocks.php

 class Stocks extends Model
 {
 protected $table = 'stocks';

protected $guarded = ['id'];
 }

stocks_with_plan.php

protected $table = 'stocks_with_plan';

protected $primaryKey = 'plan_id';

public function Membership() {
    return $this->belongsToMany('app\plans');
}

Plans.php

protected $table = 'plans';

protected $guarded = ['id'];

public function Stocks() {
    return  $this->belongsToMany(Stocks::class, 'plans_id');
}

public function Stocks_with_plan() {
    return  $this->belongsToMany(Stocks_with_plan::class);
}

Membership.php

protected $table = 'membership';

protected $guarded = ['id'];

public function Users() {
    return $this->belongsTo(User::class, 'user_id');
}
public function Plans() {
    return $this->belongsTo(Plans::class, 'plan_id');
}
 public function Stocks_with_plan() {
     return $this->belongsToMany(Stocks_with_plan::class,'stocks_with_plan','plan_id','plan_id');
 }

and using this to get my need -

 public function store(){
    Membership::with('plans', 'plans.Stocks_with_plan')->where('membership.user_id', auth()->user()->id)->where('membership.status', 'paid')->get();
}