Today's census figures will focus on international migration, ethnic groups and religion - and the Welsh language.
Some parents like Rhian Cecil hope it'll lead to more Welsh medium and bilingual schools over the next ten years.
"It's really important for us as Welsh speakers to be stood up and counted".
"Hopefully all the figures can help local councils create more provision".
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A public inquiry into undercover policing in England and Wales is to be formally opened today.
Teenage girls will be taught about body confidence, self-esteem and encouraged to get active.
A landmark hearing is expected today on a fight for compensation by more than 350 former British Coal coke oven workers.