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One way to load rows for child foreign keys in SQLite using C# ADO is to use a SQL JOIN operation to combine data from the parent and child tables. Here's an example:

Assuming we have two tables: parent with columns id and name, and child with columns id, parent_id, and value. The parent_id column in child references the id column in parent.

To load all child rows for a specific parent row, we can use a SQL query like this:

SELECT child.id, child.value
FROM child
JOIN parent ON child.parent_id = parent.id
WHERE parent.id = @parentId

Here, @parentId is a parameter that specifies the ID of the parent row we want to load child rows for. We join the child table with the parent table using the parent_id and id columns, and filter the results to only include child rows with the specified parent ID.

To execute this query using C# ADO, we can create a SQLiteCommand object with the SQL query and a SQLiteParameter object for the @parentId parameter, like this:

using (var conn = new SQLiteConnection("Data Source=mydatabase.db;"))
{
    conn.Open();

    using (var cmd = new SQLiteCommand(conn))
    {
        cmd.CommandText = @"
            SELECT child.id, child.value
            FROM child
            JOIN parent ON child.parent_id = parent.id
            WHERE parent.id = @parentId";
        cmd.Parameters.AddWithValue("@parentId", parentId);

        using (var reader = cmd.ExecuteReader())
        {
            while (reader.Read())
            {
                int childId = reader.GetInt32(0);
                string childValue = reader.GetString(1);
                // Do something with the child row data
            }
        }
    }
}

Here, parentId is the ID of the parent row we want to load child rows for. We execute the SQLiteCommand using the ExecuteReader method, and iterate over the result set using a while loop and the SQLiteDataReader object. Inside the loop, we retrieve the ID and value of each child row using the GetInt32 and GetString methods on the SQLiteDataReader, and do something with the data (e.g. add it to a list or display it in a UI).