What makes identical twins identical?
Identical twins are identical because they both came from the same egg. The term "Identical" is used as they look very much like each other and anybody can say that they are twins by just looking at them.
If you have twins and triplets in your mom's side of the family and you had twins what are your chances of having multiples?
Fraternal twins occur when two fertilized eggs are implanted in the uterine wall at the same time. When two eggs are independently fertilized by two different sperm cells, DZ twins result. The two eggs, or ova, form two zygotes, hence the terms zygotic and biovular. Identical twins occur when an egg splits into two; which makes them identical. Identical twins are not hereditary like fraternal twins can be. It is complete coincidence.
Monozygotic (Identical or Maternal) twins are identical because they came from the same egg and were split after conception but before fetal development. Identical twins have nearly identical DNA, however, environmental factors may switch genes on and off, differences are more pronounced as the twins age. Dizygotic (Fraternal) twins are not identical. They are as different as any other siblings.
Identical twins (monozygotic) occur when a single egg, fertilized by a single sperm, splits into two identical halves. Two separate babies with identical DNA are formed. Identical twins are always the same sex and blood type. http://www.twin-pregnancy-and-beyond.com/identical-twins-or-fraternal-twins.html