How to get single nested child object in parent serialized object when models are foreign key related?

I have related models like:

class ModelC(models.Model):
    name = models.CharField()

class ModelA(models.Model):
    state = models.Charfield()
    modelc = models.ForeingKey(ModelC, through='ModelAModelCRelation')

class ModelAModelCRelation(models.Model):
    modelc = models.ForeignKey(ModelC)
    modela = models.ForeignKey(ModelA)

class ModelAChild(models.Model):
    parent_model = models.ForeignKey(ModelA)
    active = models.BooleanField(default=True)
    type = model.CharField(choices=['a', 'b', 'c', 'd'])
    updated_at = models.DateTimeField()

• ModelC is related to ModelA with many to many relation,
• ModelA is related to ModelC throug ModelAModelCRelation relation,
• ModelAChild is related to ModelA with ForeignKey, which have many records related with ModelA record

And the related serializers are:

class ModelCSerializer(serializers.ModelSerializer):
    modelA_objects = ModelASerializer(many=True, read_only=False)

    class Meta:
        model = ModelC
        fields = StateBaseSerializer.Meta.fields + [
            "id",
            "name",
            "modelA_objects",
        ]

class ModelASerializer(serializers.ModelSerializer):
    modelAChild_objects = ModelAChildSerializer(many=True, read_only=True)

    class Meta:
        model = ModelA
        fields = (
            'id',
            'state',
            'modelAChild_objects',
        )

class ModelAChildSerializer(serializers.ModelSerializer):
    class Meta:
        model = ModelAChild
        fields = (
            'id',
            'active',
            'type',
        )

This approach is returning result like this:

[
    {
        'modelC_obj': {
            'id': x,
            'name': 'object name',
            'modelA_obj': [
                {
                    'id': 1, 
                    'state': 'state name',
                    'modelAChild_obj': [
                        {
                            'id': 1,
                            'active': true,
                            'type': 'a'
                        },
                        {
                            'id': 2,
                            'active': false,
                            'type': 'b'
                        },
                        {
                            'id': 3,
                            'active': true,
                            'type': 'd'
                        },
                    ]
                }
            ]
        }
    }
]

But, I need a serialized result like:

[
    {
        'modelC_obj': {
            'id': x,
            'name': 'object name',
            'modelA_obj': [
                {
                    'id': 1, 
                    'state': 'state name',
                    'modelAChild_obj': {
                        'id': 1,
                        'active': true,
                        'type': 'a'
                    }
                }
            ]
        }
    }
]

I tried many querying method with Case When approach used in Subquery. But I cant made it to fetch only one ModelAChild record to serialize. What is the proper query and serializers to return result like the above?

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