In instantiating the ImmutableString, the function pointers to the get and length methods actually refer to the String.get and String.length method, by going through the base variable which is an internally stored String object. The use of a function pointer can achieve inheritance of a method from a superclass.
Most women will start to show at some point between weeks 12 and 24 of pregnancy, with most reporting that they began to show during the first half of their second trimester, between 12 and 18 weeks.
With first time mothers, baby bumps start to show around week 12 of their pregnancy, or just as they enter their second trimester. This is the time when the baby rises out of the pelvis. However, this is not a rule. Some mothers get baby bumps sooner, some get them later. Also, some mothers try to disguise their bump.