how to use "groupBy" with relationship Laravel

Question

I need to do a grouping by date. The problem that are two tables "kanban" and "apontamentos".

something like: Kanban::with('apontamentos')->get()->groupBy('dataApontamento'); property error

enter image description here

I've tried everything, use "groupBy" in the model. Need to know how to group in the controller and do the "foreach"

closest I ever got was that way:

$days = Kanban::with('apontamentos')->get()->groupBy(function ($val) {
      return $val->dataApontamento;
  });
  // dd($days);

  foreach ($days as $day => $appointments) {
    echo '<h2>'.$day.'</h2><ul>';
    foreach ($appointments as $appointment) {
        echo '<li>'.$appointment->atividade.'</li>';
    }
    echo '</ul><br>';
  }

clearer example:

Kanban

Title: waiting for service

Apontamentos

date 05/05

Project1

Project2

Project3

date 06/05

Project1

Project2

Project6

Project7

Kanban

Title: pending

apontamentos

date: 08/05

Project9

Project8

Project4

Kanban

Title: Kanban

Title: waiting for service

apontamentos

date: 09/05

Project1

Project1

Project1

Project1

10/05

Project1

Project1

Project1

Project1

Answer 1

try this!

Kanban::with(['apontamentos' => function($query){
    $query->groupBy('dataApontamento');
}])->get();