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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England enjoyed a winning send-off to their Australia tour as they recovered from early problems leaving Wales floundering.
Veteran singer Sir Tom, 75, is gearing up for his first concerts since wife Linda died after a "fierce" battle with cancer in April.
It will be a dry and fine day across the country with plenty of warm sunshine and light winds.