My kids immigrated to Toronto/Ontario/Canada. Should I convert their birthcharts to Toronto as birth

[Astrovalley]

Absolutely NOT. Birth data is always the PLACE of birth plus, of course, the date and time they were born at that place. A new geographic location would only matter when preparing a progressed or transits chart. Simple non-astrological example: The model and year of an automobile does not change if the owner moves to another location