Yes, older than 7 years because in Portugal children are only allowed on motorcycles after 7 years of age. We also have to distribute the weight on the motorcycle, between adults and children, for balance and safety reasons. So, if there is one adult and one child as passengers, the adult will need to sit in the sidecar whilst the child rides on the pillion seat of the motorcycle. The child needs to have 1,20m or more.
Children older than 12 years have no restrictions.