Caitlyn Jenner appeared on Piers Morgan's Life Stories on Thursday night to talk candidly about her transition.
After being questioned whether she would ever date again, Caitlyn went on to say that it's not on the cards after her three marriages.
She explained her life is 'very busy' and then proceeded to tell Piers how many grandchildren she had.
But some viewers noticed that the maths just didn't quite add up.
Caitlyn stumbled over her remark about grandchildren, perhaps unsure of the total number she should reveal, and said: "I've got 12...13 grandchildren."
However, if you total up all of the Caitlyn's known grandchildren, she seemingly only has 11.
From her first marriage to Chrystie Scott, their daughter Cassandra has three children while their son Burt has one child.
Caitlyn's son Brandon, from her second marriage, also has one child.
Then we get onto the brood Caitlyn inherited with her marriage to Kris Jenner. Kourtney Kardashian has three children (Mason, Penelope and Reign), and Kim K is mum to North and Saint.
Rob Kardashian also has a child with Blac Chyna.
Could Caitlyn be hinting another of Kardashian/Jenner's has already given birth? Is Kylie Jenner's rumoured pregnancy the 12th grandchild? This would fit in with one of our theory that Kylie may have already given birth (check out all the possible explanations here).
Or perhaps she's referring to Kim's third child, which she's expecting vie surrogate, and Khloe's recently announced first baby.
These Kardashian/Jenners like to keep us guessing, don't they?
In other Kardashian baby news, Khloe's revealed the name she'll giver her baby if it's a boy.
Speaking on The Ellen Show, Khloe announced that if the baby is a boy he’ll be called Tristan Thompson Jr, after his father, but she hasn’t decided what the name for a girl will be yet.