Hi Marina Do you mean that two children with the same surname have exactly the same reference i.e. same registration district, same year & quarter, same volume number and same page reference? This would indeed be the case if they were twins, but there is a small chance they could be cousins and their fathers popped into the register office together, and a chance that it is just a co-incidence (depending on how common the name is). I have a case of twins occurring on successive pages - one must have been the last entry on a page so the other twin was on the next page. Good luck, Ingrid > Found two birth registrations with the same numbers in 1925, on Free > bmd. These may have been twins, so do twins share the same birth > registration number? >