Identical twins are always the same sex. They start life as one egg inside their mother. The egg breaks in two and, nine months later, two babies are born. They are exact copies of each other. There is one pair of identical twins for every 300 births. This means there are about thirty million pairs of identical twins in the world today!
   Diana and Monica Petrungaro are twins.Their birthdays are thirty-six days apart. Diana was born on 22 December 1987 and Monica was born on 27 January 1988.
   Greta and Freda Chaplin are English twins who have 'one mind in two bodies'. They talk at the same time, wear the same clothes, and sleep in the same bed.

   Fraternal twins are different. They come from two different eggs and can be the same sex or different sexes. In England there is one pair of fraternal twins for every 150 births.
   There are more fraternal twins in some countries than in others. In the Yoruba tribe in Nigeria there is one pair in forty-two births. In Japan there is one in 160 births. Scientists don't know why there is this big difference.
   In 1961 Mrs Pearson from Florida had her seventh set of twins!
   Mrs Vassilyev from Shuya, Russia (1707-1782) had sixteen pairs of twins, seven sets of triplets, and four sets of quadriplets.
   Charles and George are the 'calculator twins'. Tell them a date in the last or next forty years and they can tell you which day of the week it was or will be. Empty a bag of coins on the table and they can tell you in two or three seconds how many there are. They don't count, they see the number!