First Minister Carwyn Jones has led Welsh messages of congratulations to the Duke and Duchess of Cambridge.
"Many congratulations to the Duke and Duchess of Cambridge on their wonderful news" he tweeted.
The Leader of the Welsh Conservatives in the Assembly, Andrew RT Davies, also tweeted a message of support, describing the news as "the perfect end to a Jubilee year.
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Carwyn Jones will try to focus Labour members' attention on their party's achievements in Wales in what could be a tense conference.
Much of Wales again enjoying a fabulous day with warm sunshine! A little cooler in the west where the mist and low cloud will linger!
Delyth Thomas, aged 56, was overwhelmed when her cat Chloe walked back into her house in Skewen after four years.