public function sort()
	{
		usort($this->allEvents, function ($event1, $event2) {
			if ($event1->getStartDate() == $event2->getStartDate()) {
				return $event1->getId() < $event2->getId() ? -1 : 1;
			}

			return $event1->getStartDate() < $event2->getStartDate() ? -1 : 1;
		});

		return $this;
	}