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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The training centre and headquarters of Girlguiding Cymru in Powys, is laying claim to having the tallest living Christmas tree in the UK.
Cloudy with rain and strong winds, local gales along exposed coasts. Rain persistent across western hills, and becoming heavy later.
It will be cloudy with hill fog and mild overnight with increasing winds, with gales around southwestern coasts.