Help with booster seats

We are living away from oz, but coming back in October for a holiday.

I'm just trying to get my head around the new laws and what I need for DS. I have a seat for DD.

I know the weight and age is supposed to be 7years and 26kg.... DS will be 5 but already weighs 25kg.

What will I need for him? He's not tall enough for just a regular booster seat with adult belt (plus I'm not comfortable with that anyway)

I'm looking at getting the infa-secure tri-max delux expanding booster seat. Does anyone have this seat, do you think it would be suitable for DS?? Would I have to get him a harness thingo? This seat would have to last for when we do return home permanently (hopefully sooner rather than later!)

Help!

(mods please move if in the wrong spot)

We just moved DS1 into a Safe and Sound Hi liner with a harness. He is 4 and 16kg. (We needed to move DS2 into Maxirider and DS1 was going to be too tall for Maxirider in 6 - 12 months anyway.

DS is using his maxi rider here, but will be too tall for it very soon. DD will have it in the future as we won't be able to bring her Maxi Cosi seat as its not Australian standard (no anchor point).

Our 4 year old uses a Safe n sound Hi Liner. We also bought a harness for it, but it was such a pain to do up and it didn't sit properly near his neck. He asked us how he was meant to sleep in his seat with the harness on. I did some online research and apparently, the harnesses that you add on, aren't much chop, as most people don't install or do them up properly and the one we got just irritated his neck. So, we just use the adult belt and his seat has an anti-submarining clip to stop it riding up his abdomen in the event of an accident.

Another here using the S&S Hiliner, DD is 5 and 19 kgs and we have found that although I was nervous about it, it fits her super well, even when she has fallen asleep it fits really well and looks safe and comfortable. I also read about the H-harness being no safer than a lap belt at this age and weight and actually LESS safe if it's fitted incorrectly and sits incorrectly which a lot of the time they are because they are so tricky to do up. I would be possibly emailing the companies whose seats you are looking at and see what they recommend seeing as he is near the upper weight limit for them all. xoxox

Thanks for all the info everyone. Does anyone know the difference between the high liner, and the high liner SG?

I guess for DS weight, and height, he would only need the car seat belt around him then? His age being only 5 would not be a factor in needing harness???

Pretty sure age isn't a factor, in Vic anyway it goes off weight and also height as their shoulders need to be higher than the marker on the seat. Mist stares are similar I think. Pretty sure they are the same seat, mine is the SG.

Not sure if this helps, but we got a converter from RACV which lets us change a lap/sash seatbelt to an H-harness. It was about 30 bucks, and you can get them posted out.

Yeah they are essentially the same, there was 1 small difference my friend who works for them told me but I don't remember sorry... Is say tho if u can pay the extra $20 or so & get the 'grey frost' its worth it. Especially if ur ds is going to eat in the car at all coz the coloured ones have a kinda mesh fabric that crumbs etc would love to stick in! Also my ds1 uses it & has for about a year & never needed H harness because of his height, it just would've made life difficult iykwim :)