C#/Linq/SQLite Recursive query to build a family tree

const int MaxLevel = 6;	// Maximum depth
List<Animal> animals = new List<Animal>();		// Return
List<Animal> animalData = new List<Animal> {	// Database
		new Animal (1, 98, 97, 0),
		new Animal (2, 98, 97, 0),
		new Animal (3, 98, 97, 0),
		new Animal (104, 98, 97, 0),
		new Animal (98, 101, 102, 1),
		new Animal (97, 4, 10, 1),
		new Animal (101, 60, 44, 2),
		new Animal (102, 11, 6, 2),
		new Animal (4, 57, 22, 2),
		new Animal (10, 66, 21, 2)};

void Main()
{
	GetAnimal(104);	
	animals.Dump();
}

// Add one animal record to the list of ancestors. Recursively called.
void GetAnimal(int id)
{
	var animal = animalData.SingleOrDefault(s => s.AnimalId == id);
	if (animal == null) return;	// Stop recursion (not found)
	animals.Add(animal);
	if (animal.Level == MaxLevel) return;	// Stop recursion (max level)
	GetAnimal(animal.MotherAnimalId);
	GetAnimal(animal.FatherAnimalId);	
}

public class Animal
{
	public Animal(int animalId, int motherAnimalId, int fatherAnimalId, int level) // Constructor
	{
		AnimalId = animalId;
		MotherAnimalId = motherAnimalId;
		FatherAnimalId = fatherAnimalId;
		Level = level;
	}
	
	public int AnimalId {get;set;}
	public int MotherAnimalId {get;set;}
	public int FatherAnimalId {get;set;}
	public int Level {get;set;}
}

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