Some infectious diseases of course are contagious or perhaps both are exposed to the same thing causing the illness eg mosquito bites causing Malaria. However DO NOT TREAT A CHILD IN ANTICIPATION!! Always wait and then see a doctor! Never assume it is the same illness. You may be wrong! It is also not automatic that the child will be sick at all

Though gene and heredity has a major role to play when it comes to conceiving twins. Some couple also opt for IVF. U can see a fertility specialist for more info.