Which is the safest option here?

[Bramshott]

DD2 is 4 and weighs just under 15kg. We're off on holiday soon, with quite a lot of driving and are trying to work out if she will be safest in her old Stage 2 seat (which was bought new for DD1 in Jan 2004 so is fairly elderly now) with a 5-point harness, or her new High Back Booster seat we've already got, but which she's slightly under the weight for.

Any opinions?

if she is under weight for the booster its very dangerous to put her in it.
cars seatbelts are approved with a minimum weight of 15kg,if she is under this,it may not work properly.Its also not legal for her to use a seat which isnt suitable for her.
she needs to be in a 5 point harness,although if the seat she was in is 7yrs old i wouldnt use it.

personally i would buy her a highbacked booster with a harness(which we had to do for our dd as she was too tall for her stage 2 seat at 2yo and 13kg) as i wouldnt be happy using either seat for her.

Hmm. Thanks for your reply. I appreciate that neither option is perfect, which is why I was asking. Buying another seat isn't really an option, so I was just trying to work out which was the best (maybe I should have phrased it as 'least worst'!) option out of the two we have.

Neither are safe.

If she uses the HBB and you have an accident the seat belt may not engage (lock) and your daughter may be flung forward into the passenger compartment of your car. If you use a seat against manufacturers recommendation (i.e. under the min. weight) then your insurers/other party's insurers would refuse to compensate your child for any injuries/result of the crash.

If she uses the expired seat and you have an accident the plastic shell of the seat may break and the harness rip though it, ejecting your daughter from the seat and into the passenger compartment of your car.

You say the seat was purchased in Jan 2004, but it was almost certainly manufactured in 2003 or even earlier. It will say on the seat (date clocks/dials or a grid with 'pips' to indicate the date). The older the seat the more likely it is the plastic has started to degrade.

I have just stripped down a baby carrier to take to the tip as DD3 has out grown in. It was manufactured in June 2006 yet it had stress marks on the shell already. It may not be that obvious to see the degradation of the plastic so not even a visual check may be good enough. Also the harness may weaken and the fibres become stretched with the force of an impact if they are of some age.

You best option would be as sazm says - get a harnessed high back booster. You could also try returning her new HBB for store credit/refund as they sold you a unsuitable seat.

could you borrow a harnessed HBB from a friend?

I have to admit that I wouldn't be happy with either of the options you have, so couldn't in all honesty recommend one over the other.

tbh you would be safer buying one of the cheaper high backed boosters with side impact and a harness,kiddicare have some cheap as do argos etc :)

Thanks thisisyesterday - that might well be the best option. I take the point that neither seat is really suitable for a substantial journey.

I'll also keep feeding her the cream cakes to try and get her up to the magic 15kg!

neither seat is suitable for any journey tbh, an accident can happen 2 mins from home.

how far off 15kg is she?

She is over 14kg with no clothes, so I need to weigh her again with clothes and shoes (presumably they all count?).

i would think so,she will be wearing them when she is in the seat, (well i assume she will lol)

I'd probably use the group 1 seat. Considering they are intended to last for a period of around 3 years and most people use them for two or more children I would be really surprised to find one was battered (just through everyday use) enough to be unsafe after 7 years. Obviously a new seat would be better, but that's what I would use.