Thanks for the info. That's helpful. I was thinking about the middle 2 but worry the parent on one of the middle will be cut off and won't be able to get to the other parent or child unless they walk all the way around to the other aisle... But I guess the other parent could do this.

We won't be using a car seat. He's very mobile now so will just be in his seat alone with no seat and not infant in arms. Obviously sitting with us for take off and landing as required