Couple of problems:
1) the rsGchild only returns the date columns:
SELECT cars.From_dt, cars.To_dt
FROM cars
ORDER BY cars.From_dt
it needs to return the model column as well:
SELECT cars.Model, cars.From_dt, cars.To_dt
FROM cars
ORDER BY cars.From_dt
2) In the Create Dynamic Array(rsChild), the Child ID is bound to the Make column, it should be set to the model Column instead.