Would you move 6.5 year old to FT booster?

We are expecting #4 any day now and recently installed the infant seat in our '09 8-seater Sienna.

So we have...

Middle row:

Infant center, FF Size4Me behind driver for 4.5 year old, passenger side seat removed for ease of getting to the back.

Back row:

FF Nauti harnessed for 6.5 year old passenger side, RF MR65 for 2 year old driver side.

The only tether anchors are where the Nauti is now, and in the mostly useless center position, thus the RF MR behind the driver in the third row.

Getting my two year old in and out of that spot in the back row is a pain in the rear. I'd like to have both older kids in the third row, to make putting the two year old in her seat easier, but that would mean moving my 6.5 year old into a booster full time.

He's been training in an Affix with SS and has been doing great, even while sleeping, but he hasn't outgrown the harness on the Nauti yet (maybe 3/4 in left) so I feel hesitation about full time boostering him.

I know there's no research to support a 6.5 year old being safer in a harness vs. booster, but what would you do? Move him to booster or suck it up until he outgrows the harness?

He is 6.5 years old, doing great in his Affix (even while sleeping), it will make your life easier.....................YES YES YES I would put him in a booster without hesitation!

I would absolutely put the 6.5 year old in the booster. It sounds like he is ready, and there is no evidence for increased safety either way with a kid that age.

I would absolutely move to a booster in that circumstance.

I would booster, but hang onto the current seats just in case he starts to have difficulty once the novelty wears off.

I would booster without a second thought.

Thanks everyone! I'm going to make life easier on myself and switch him to the booster in the van.

I would booster without a second thought.

However, there are some solutions to that middle spot, if you want to continue harnessing a bit longer. How much does your 4.5 year old weigh and what are the weight limits for latch on the seat he is currently in. Toyota from that year defers to the manufacturer of the child restraint, so it's possible you may be able to use the lower anchors along with the too tether in that spot with ease. I find that spot very easy to use with latch if you don't need a seat next to it.

Another option is to pick up a radian. It is a bear of an install but it does for in that spot installed with the seatbelt. I can even get a backless booster next to it on the driver side.

Both those installs will allow you to use whatever seat you want on the passenger side.