Create component first and then attach to an actor (reattach transient component to actor)

Development Programming & Scripting C++
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I need to create a component first and then attach it to an actor. The component might have child components created in same fashion.

The problem here is if I try something like this:

	auto world = GEditor->GetEditorWorldContext().World();

	FTransform transform;
	transform.SetFromMatrix(FMatrix::Identity);
	auto actor1 = world->SpawnActor<AActor>(AActor::StaticClass(), transform);
	actor1->SetActorLabel("Root Actor");

	auto rootComponent= NewObject<USceneComponent>(actor1);
	actor1->SetRootComponent(rootComponent);
	rootComponent->SetWorldLocation(FVector(0.0f, 0.0f, 300.0f));
	rootComponent->RegisterComponent();

	auto subComponent = NewObject<USceneComponent>(actor1);
	subComponent->SetWorldLocation(FVector(0.0f, 0.0f, 600.0f));
	subComponent->AttachToComponent(rootComponent, FAttachmentTransformRules::KeepWorldTransform);
	subComponent->RegisterComponent();

	//TStrongRefPtr<UPointLightComponent> 
	auto lightComp = NewObject<UPointLightComponent>();
	lightComp->Rename(0, actor1);
	lightComp->AttachToComponent(subComponent, FAttachmentTransformRules::KeepWorldTransform);
	lightComp->RegisterComponent();

	actor1->AddInstanceComponent(subComponent);
	actor1->AddInstanceComponent(lightComp);

Then the component that was created with NewObject (i.e. with transient package → in this example it is lightComp) disappears, likely killed by GC.

Is there a way to create and reattach component to an actor without creating the actor in advance (as standard pattern is to specify the actor as component owner)?