My DS1 is 4. He has the Recarro car seat and is, I suppose, tall for his age (born big and stayed solid). His legs ache on long car journeys as they just hang down. On last one they got "sore", I guess he got pins and needles so thought we'd be able to buy a foot rest. I can only see one or two on the market. Am I missing them or they called soemthign different?