The Clek Foonf is one of the safest seats on the market so I think it's well worth it to buy the infant-thingy. You should be able to keep your child rear facing for at LEAST 1 year if not 2 before Toddler that's 3 plus. I would keep them rear facing as long as they fit the weight and height ranges. It's the safest way for them to ride in the car.