(a) Subsequently Born or Adopted Children. Whenever a child shall have been born to or adopted by a testator after the testator has made his or her will, and the testator shall die leaving the after-born or adopted child not mentioned or provided for in his or her will either specifically or as a member of a class, the testator shall be deemed to have died intestate with respect to the child. The child shall be entitled to recover from the devisees in proportion to the amounts of their respective shares, that portion of the estate which he or she would have inherited had there been no will.
(b) Pretermitted Children. If, at the time of the execution of a will, there is a living child of the testator, or living child or issue of a deceased child of the testator, whom the testator shall omit to mention or provide for, either specifically or as a member of a class, the testator shall be deemed to have died intestate with respect to the child or issue. The child or issue shall be entitled to recover from the devisees in proportion to the amounts of their respective shares, that portion of the estate which he or she or they would have inherited had there been no will.