When Zoey Parker gave birth to her son on the same day as her sister Courtney she beat odds of 125,000 to one.
But what is even more extraordinary is she gave birth to her first son in 2007 on the same day as her elder sister Tammy.
This time around Zoey, 23, had been due two weeks after her 16-year-old sister Courtney but went into labour early.
Hours after she cradled Riley Williams in her arms for first time, her younger sister was being rushed into the same ward at Newcastle's Royal Victoria Infirmary.
The pair gave birth 12 hours apart, with Riley being born at 9.45am on July 30 and Robbie James Armstrong making an appearance at 10.45pm.
Courtney, from Heaton in Newcastle, said: 'The whole family were shocked, I wonder what the odds are for it happening twice! Talk about history repeating itself.'
In 2007, the eldest sister Tammy gave birth to Logan on the same day that Zoey had her first son Michael. To cap it all, the family's Staffordshire bull terrier Bella had 11 puppies.
Courtney added: 'When I arrived at the hospital the staff said "Oh, we've already had a Parker in here today".
'I was like, "Yeah, I know, she's my sister!". I think the staff were all really surprised.
'Nobody could quite believe it when I gave birth a couple of hours later. It's a coincidence for it to happen once, but twice? No puppies this time, though.'
While Zoey was able to go home straight away Courtney was kept in for five days.
'Robbie had to spend a while in the special care unit when he was first born, which was worrying. He's absolutely fine now, though,' Courtney said.
'It's been great having Zoey going through all the newborn stuff at the same time. I think my parents couldn't quite believe it had happened again!
'Tammy and Zoey gave birth closer together, but they were in different hospitals, unlike this time.'
Robbie is the first child for Courtney and her boyfriend Robert and Riley is the second child of Zoey and partner Michael, now living in Hamsterley Colliery, in Durham.
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