The twins who have different dads

Alexandra and Calder are 19-month-old twins who have two different biological dads.

Their dads - Simon and Graeme Berney-Edwards - are one of a very small number of British couples who have chosen to fertilise one embryo each during IVF, and then have both implanted into a surrogate at the same time.

They explained how it worked.

Watch the Victoria Derbyshire programme on BBC Two and BBC News Channel, 10:00 to 11:00 GMT - and see more of our stories here.