If a passenger has a child who is under the age of 7, drivers are allowed to cancel the trip if they do not have appropriate child restraints or booster seats.
If a child is aged between 7 and 16 years of age and too small to be restrained by a seatbelt, drivers are allowed to cancel/reject the trip if they do not have booster seats.
Ultimately, it is the responsibility of the driver to adhere to road rules such as mandatory child seating.