I have looked into this further and contacted the manufacturer of the car seat. They recommend changing the seat after 10 years (as long as it has not been in an accident). It seems different manufacturers have different lifespans for their goods, so best to check.
The Devil In The Family: The Fall of Ruby Franke - BBC IPlayer
Labelling cake tins or cutlery you have loaned.
Daughter not allowed to know new baby’s name until she visits him
