I agree that a double is always a better option. Like previous people said its probably not going to be used for both kids at the same time. I have 2 year old and I went with a 2 seater burley encore. I found that he can sit in the center of the trailer and have extra space on either side, he can lay at an angle while still being strapped in. It also allows you to carry more stuff if you want. I carry snacks, drinks, a blanket, a small pillow, and a few toys for him. With all that stuff there is still tons of room in case I need to carry other items.