A mother of twins has had a shock after doctors revealed that her 11-month-old boys do not have the same father.
Paternity tests then revealed what had happened - two eggs had been fertilised by two different sperm and there was a 99.99% chance the twins had different dads.
Doctors at the DNA lab in
Mia later admitted she had had an affair and got pregnant by two different men at the same time.
She told TV channel Fox 4: "Out of all people in
Clear Diagnostics president Genny Thibodeaux said: "It is very crazy. Most people don't believe it can happen, but it can."
Sky's health correspondent Thomas Moore explains: "A woman can release two eggs from her ovaries, and the eggs will remain viable for 24 hours after ovulation.
"Sperm can survive up to five days inside a woman's body, so a woman could sleep with different men several days apart, and get pregnant not once, but twice."
And while it sounds rare, recent research indicates that one in 12 non-identical twins are so-called bi-paternal, with a rise in fertility treatment and changing sexual behaviour being blamed.
Mia's partner James Harrison is father to one of the boys.
He told Fox 4 that he had forgiven his fiancee for having the affair and intended to raise both children as his own.
However, he admitted it had been tough discovering the truth.
"It's a day by day thing. It's going to take time to build the trust like we had," he said.
The couple plan to tell the twins they are half-brothers when they are old enough to understand.skynews