Does anyone have a narrow booster seat-- to fit in b/t two other car seats?

Looking for one, if possible, to have on hand so I can maybe car pool every now and then.

Can I even fit one in the middle? I have a fairly wide car, but no third row.

Thanks!

Does anyone have a narrow booster seat-- to fit in b/t two other car seats?

If you have a head rest in that position, you could try a bubble bum in that spot. You'll need to make sure you can buckle the child in. If you don't have head support in the middle you'll need a high back booster there if the child you intend to transport's ears are even with/over the back of the seat, or you'd have to rearrange your seats. If the seats you have now won't work you may be able to replace one/both and get 3 across.