Convert to booster or buy Frontier85


New member
He wasn't supposed to grow so much, just yet. :)

My 6-year-old first-grader is even with the top slots on the Prosport! He's 48.5 inches and 54 lbs. The seat must also fit his sister, who is 40 lbs. and will be 5 November 1 and is in preschool. This is the spare car, a 2005 Civic, used on weekends regularly.

So I'll either get the Frontier85SiCT, or convert to booster mode with Prosport.
Help me decide.

We plan to get a new car in the next year or year and a half, and do 3 across so the Frontier will have no place. And with no side air-bags, I would get the SICT for sure.
So I guess I know my options and just need some opinions. I'm so indecisive!


New member
what I would do is convert the prosport... I'd give him a week or two to see how he does... if he's mature enough to stay put and the seatbelt fits, then I'd leave him that way.

if not, I'd put the harness back in.

for the 4yr old, I'd use a seat with a harness.


New member
I would convert. He's a big kid. And I think in a week or two, you can teach him to ride appropriately at 6 yrs old. My 7 yr old isn't even as big as your 6 yr old. We boostered him at 6 and 40 lbs. Even w/him having high functioning autism, he's still done really well.


New member
He is fine in one.
But given it needs to work for the two kids...I'm thinking Frontier.

Any of them can get wild around siblings! :)


Senior Community Member
Do you mean that both kids will use the same seat at different times or that sis needs to fit in the backseat as well? As long as your ds sits well in a booster, I'd convert but I'd probably find something else for sis.


New member
I would buy a cheaper high back booster for your son, especially since it's a secondary vehicle, and keep the Prosport in there for your daughter.


New member
I was not clear! :)
Sorry if I was not clear, lol. The seat must work for BOTH 6-YEAR-OLD and a soon 5-year-old 40 lb. kid. They use it at different times all weekend. There is a harnessed Prosport on the other side for 3-year-old (and the almost 5-year-old can use it too). They both fit in that.

See, the issue is the Civic has to fit any combo of the 3, 6 and almost 5-year-old.
(Swapping seats is not an option. 1, we go in and out too quickly that changing and installing seats would be crazy, and 2, I'm pregnant with back issues so it's one seat only, and it'll stay put).

At any rate, I have a tiny bit of time based on his shoulders. Very tiny, but a few months maybe.


New member
Then I would convert one prosport to booster mode, and have the oldest kid ride in that. So if you take the 3 and 5 year old the 3yo sits in the harnessed one and the 5yo sits in the boostered one. But if you take the 6yo and the 5yo, you can put the 6yo in the boostered one and 5yo in harnessed one.


New member
That's exactly what I was thinking. It's not often at all the 3 and 5-year-old would ride together, anyway.


New member
I started having my oldest ride in a booster for short rides very occasionally when she was almost five, and now she is 5.5 (turning 6 in feb) and she is doing so well that I have her in a booster in both vehicles. So I don't think it's totally unreasonable. I still have a FR85 in our storage for those longer trips though just in case :)

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