The retired sprint great is now one kid short of a very cool-sounding relay team.
The rare phenomenon is known as superfetation – and it recently happened to Rebecca Roberts from Bath.
Birth Diaries: 'I went into labour early – at six months, 27 weeks and four days to be precise.'
Delivery nurse Tara Drinkard told the new mum, "Guess what? ... My sister is a twin and we are both going to be in your delivery.”
"My second twin was immediately taken to NICU because of breathing problems."
The operations added up to more than 50 hours of surgery time.
Cue: a lot of high-pitched screaming.
"This shows that there is life after Ebola."
The only thing cuter than an adorable baby is two babies, right?
"Hideously grateful is how I would describe my birth."