Laravel - 基于关系的事件

I have the following models.

1. Shipment
2. ShipmentPiece

A Shipment can have multiple ShipmentPiece instances. A ShipmentPiece belongs to a Shipment.

Is there a model event (same as creating or saving) for when I attach a new ShipmentPiece to a Shipment?

For example, when I do:

$shipment->shipmentPieces()->save($shipmentPiece);

or

$shipment->shipmentPieces()->saveMany([$piece1, $piece2]);

I would like to run some logic in the Shipment class, inside the boot method.