My 4 year old and 17 month old are both still rear facing. My 4 year old is still has a bit of height and like 8 pounds left until he reaches the weight limit on his Diono Radian RXT . They're both in Radian RXTs, and my 17 month old has SO MUCH ROOM and doesn't weigh all that much still so I'm so glad. She is so happy in that seat, and so is her brother. I'm going to probably get a new seat for my 4 year old for forward facing then give this baby his Radian though or get another one. I LOVE these seats!