The Take That singer took to Twitter to share his exciting news.
First of all he teased fans...
Some of Donald's followers hoped new tour dates were about to be announced, but other eagle-eyed fans claimed to have already known about Halil's pregnancy having spotted her with a "baby bump" in Newcastle.
Then 10 minutes later he revealed...
Along with the month the baby is due...
Which would mean Halil is around four to five months pregnant.
This will be Donald and Halil's first child together, but the singer is already the father of two daughters from previous relationships: 16-year-old Grace and 10-year-old Lola.
Grace's mother is Victoria Piddington, while Marie-Christine Musswessels, who he split from in late 2009, is the mother of his second child.
Donald first met Halil when Take That filmed a Marks & Spencer Christmas TV advert in 2008, but they only started dating two years later and they wed in a secret ceremony in January 2015.
Donald has promised that when the baby arrives there will be a special edition of his regular #thingsonhowardshead photo.
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