
Cosco Kids
Scenera Next DLX Convertible Car Seat
Super light, cheap, great for air travel, but outgrown fast.

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I have three boosters in my ‘24 and it is tight. Three full-size, double cupholder childseat Britax will not fit (have them and tried). To get the fit you have to buy special slim seats and I’ll second the mentioned Diono brand.
Yes. Diono radian 3 across Did it for years thank me later
We have 98 and 99th percentile kids and Diono car seats have saved us so much. We had a Graco baby car seat with base even though the Diono has insert for infants. It was just easier to carry baby and we used it for both kids as the were close in age. They are giant 3 and 5yos now and with the long expiration date and weight limit of 120lbs, they’ll be in them until high school. Second hand baby Bjorn bouncer was amazing. Anything food or potty related get the least complicated smoothest surface area products for easy cleaning. Ikea high chair, little partners wooden booster seat, and one piece potty seat.
We loved our Britax Boulevard but it was not at all good for bigger kids rear facing longer! I think the weight limit was 35 on latch install which some of my kids hit before age 2. We had to change to Diono Radian and Graco Extend to fit to keep them rear facing.
I’d recommend 3x of the diono seats. Their whole marketing thing was that you can fit 3 across in most cars. I found them easy to take apart to clean as well, although maybe that was because we just had so many and we did it a lot of times it got easy. On our last trip which had like a 3 hour drive each way, my wife was like “we should clean the car first”… I was like it’s just gonna be covered in damn snacks as soon as we leave the driveway, why bother.
Make sure you get the Slimfit3LX. The "regular" Slimfit is actually too wide for 3 across. In order to get 3 across in almost every vehicle, you'll need to use the seatbelt install for all 3 seats. That allows you to pull the side seats closer to the door to maximize space. (You also must seatbelt install when the child hits the maximum weight for lower anchors as well-- often but not always 40lbs-- so it's wise to get familiar with doing that as eventually you will need to do it all the time.) With rental cars, you'll want to look for the biggest vehicle you can to maximize the likelihood of the seats fitting. So a large sedan instead of an economy or compact, for example. 3-across installs I've personally had good luck with: - Chicco Keyfit, 2 RF Slimfit3LX - 2 RF Slimfit3LX, FF Chicco MyFit - RF Slimfit3LX, FF Diono Radian, RF Slimfit3LX Keep in mind that the Slimfit tends to tilt slightly when installed rear facing with the seatbelt. This doesn't affect the safety as long as it is tightly installed (moves less than an inch at the belt path when you give it a handshake with your non dominant hand). But don't be surprised when it happens! It's just an annoying bug with that particular seat. Forward facing it's doesn't have that issue.

Cosco Kids
Scenera Next DLX Convertible Car Seat
Super light, cheap, great for air travel, but outgrown fast.

Cosco Kids
Scenera Next Convertible Car Seat
Portable, affordable, quickly outgrown, airplane buckle discomfort.

Joie
Mint Latch
Easy baseless LATCH install, lightweight, but quickly outgrown.

Nuna
PIPA Series
High-end travel, easy baseless install, but very pricey.

WAYB
Pico™ Portable Car Seat
Ultra-light, compact travel, quick install, but expensive and outgrown fast.

Ranked #1
Cosco Kids - Scenera Next DLX Convertible Car Seat

Ranked #1
Cosco Kids - Scenera Next Convertible Car Seat

Ranked #1
Cosco Kids - Scenera Next DLX Convertible Car Seat

Ranked #1
Doona - Doona Series

Ranked #1
Cosco Kids - Scenera Next Convertible Car Seat

Ranked #1
Nuna - PIPA Series