Ok, I know what the law says: http://www.childcarseats.org.uk/law/index.htm And when in the car all is fine. However, in the back of Daisy-Mae, the booster seat means the seatbelt comes up & over her shoulder at all the wrong places & slips off constantly as being 8 she doesn't have broad shoulders!! And on the rare occasion she does doze off it's a disaster! She would be far safer & more secure without the booster seat but is currently 'only' 126cm tall & unlikely to grow 9cm by the time we're properly out & about in Daisy-Mae. We can't be the only ones who have this problem ... help!! Thanks (Then there is the Spanish & French law to contend with but that's not until August so I'll worry about that nearer the time!).
Hopefully at 8 she's growing fast! We had the same trouble and TBH we ditched the booster seats in favour of not maiming our kids in a crash. Sod the law, sometimes common sense must win out.
Don't use it then. But keep it in the van if you get stopped you can demonstrate. Any reasonable person if you treat them with respect would see your viewpoint.
These may help http://thelatebay.com/index.php?threads/uber-rare-rear-3-point-inertia-seatbelt-bracket.18366/
