RSTV vs HBB for 4.5yo?


Active member
I have a 3 across situation. DD1 (4yo) is in a FR85, DD2 (2yo) is in a RF Radian and I intend on keeping her that way. I have a baby coming in September and can't fit another car seat in my car. I've tried a MyRide because of the narrow base and it was a no-go, as well as a few infant seats. None work, they hang off the seat, or don't fit if they are put in the middle.

When babe is born DD1 will be 4y9m and DD2 will be 2y9m. DD1 has outgrown the Radian by weight RFing and by height FFing. There is no slimmer option for a harnessed seat.

My options are a booster and a RSTV.

I dislike the idea of using a RSTV for full time use, and since my belts don't lock, the new ones don't have a lockoff, and I don't have top tethers (and Ford won't install them) I am not comfortable with the idea that DD will be uncomfortable and wiggle around. It's also a battle with her and the chest clip and crotch buckle- but she has become okay with it. She has sensory issues and I'm not sure she'd be okay with something that buckles way more.

I am much more confident that with booster training she will learn to stay in place in a HBB, which will obviously be more comfortable.

I am truly more comfortable with a "shell" around my daughter, and even though there are no SIP standards.. I still feel more comfortable with it.

That said.. DD does have some control issues, but they haven't been with "safety". Safety is not something she takes lightly- she is a very careful person. And with THAT said.. she does occasionally fly off the handle at home when she can't control a situation, she flies into a fit of uncontrollable rage... but she has never ever done it in the car. She really enjoys being in the car and is always a pleasant child to be around.

So I'm sort of lost. I have people telling me that I should absolutely NO WAY put her in a booster because she'll for sure wiggle out of place. But there's no real way to know unless I buy a HBB and start to train her- right?



Well-known member
If I were in your situation and had your child, I'd likely go with a HBB. The RSTV just isn't my idea of a good option for every day use. If she'll sit correctly in the HBB, I'd got for it.


New member
Is it possible to get 2 RNs in with the Frontier? I personally am not comfortable with a not yet 5 yo boostered full time, and I think that would only make your 3 across more difficult on a daily basis.


New member
Are you sure your oldest has completely outgrown the radian? You can use it with the shoulders above the top position- until the ears are even with the top of the shell and the child is 53 inches tall.

A booster is a pain in a 3 across. I can fit a frontier, where it would be difficult to buckle a booster.

I love the rstv, but not for long drives- and to me, it's more like a different form of booster. The kid can still wiggle out of place and it's not very comfortable.

I would also try different infant seats and convertible seats for the baby to see if one could fit with the current setup.


Active member
I can't fit two Radians rear facing in there- they are too wide at the sides of the shell. I would be able to get a FFing radian outboard, RFing radian center, and then the FF outboard on the other side, however, I'm not comfortable with turning my teeny 2yo FFing, I'm wanting to leave her that way until she's near 4 if she's less delicate looking. I know it has to do with her bones.. but I'm just not comfortable with it until then. That would be my plan, actually, once the baby is bigger- get another Radian and FF my now 2yo.

I have a no-back turbo (for driving around older kids when we use my MILs truck, obviously DD would be in a HB) and took the FR85 out, moved the Radian over a little (closer to the side where the booster would be) and I was able to buckle it fine. I also put the Radian outboard and there was ample room in the center for another seat- I could probably get a MyRide in there just fine, or an infant seat (a narrower one like the BabyTrend, but a snugride might work.

If it did end up being difficult to buckle, I'd just leave it buckle and have her slip under the belts to get into the seat (by pulling them out all the way- my belts don't lock when you do this so that's not an issue!), and then take the slack out once she was properly positioned.

She is over the top slots in the Radian and regardless of what SK/Diono say... I'm just not comfortable with it.

Again, this is all given she learns to sit properly in it.


Active member
Will 2 Radians fit RF with the FR in the middle?

Probably, but I can't put a RF seat behind my husband, especially not a radian. If the radian is reclined (in the case of the newborn) it will push my tall husband too far up. If it is upright (in the case of my 2yo) it pokes up over the top of the seatback, right smack in the middle of my husband's head (not comfortable and incredibly dangerous in a collision). The vehicle seats don't have a detachable headrest- it's all one piece.


Active member
Hm. why is this posted in Car Seat Chat? Did someone move it or was my brain just not working correctly last night =P


New member
Did your siggy just say '95 Explorer or am I confusing myself? In a '95, I would assume forceful bracing is allowed- is it possible to get a RN at an acceptable angle for the 2 year old behind the driver forcefully braced but not sticking over the headrest?

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