Loading related objects in memory (without an ORM)

I am using ADO.NET to read a bunch of data from the database into in-memory objects.

This is my domain model:

// Question.cs
public class Question
{
    public int ID { get; set; }
    public string Title { get; set; }
    public string Description { get; set; }
    public IEnumerable<Tag> Tags { get; set; }
}

// Tag.cs
public class Tag 
{
    public int ID { get; set; }
    public string Name { get; set; }
}

On retrieving the list of Questions, I would like to fetch the related tags for each question. I am able to do this as follows:

// QuestionRepository.cs

public IList<Question> FindAll()
{
    var questions = new List<Question>();

    using (SqlConnection conn = DB.GetSqlConnection())
    {
        using (SqlCommand cmd = conn.CreateCommand())
        {
            cmd.CommandText = "select * from questions";

            SqlDataReader reader = cmd.ExecuteReader();

            while (reader.Read())
            {
                Question question = new Question();
                // Populate the question object using reader
                question.Load(reader);

                questions.Add(question);
            }
            reader.Close();
        }
     }
    return questions;
}


// Question.cs
public void Load(SqlDataReader reader)
{
    ID = int.Parse(reader["ID"].ToString());
    Title = reader["Title"].ToString();
    Description = reader["Description"].ToString();

    // Use Tag Repository to find all the tags for a particular question
    Tags = tagRepository.GetAllTagsForQuestionById(ID); 
}

    return questions;
}

// TagRepository.cs
public List<Tag> GetAllTagsForQuestionById(int id)
{
    List<Tag> tags = new List<Tag> ();
    // Build sql query to retrive the tags
    // Build the in-memory list of tags 
    return tags;
}

My question is, are there any best practices/patterns for fetching related objects from the database?

Most of the SO questions I came across for loading related data provide the solution for entity framework. There is no answer for this duplicate question.

Even though my code works, I would like to know other ways to do the same. The closes explanation I came across that's targeting my particular problem was Martin Fowler's Lazy Load pattern, but I am not sure how the implementation will look like.