Children Born After a will
A child born or adopted after the parent has made a will that does not include that child is known as a "pretermitted child."

Pennsylvania grants pretermitted children with the right to take the same portion of the parent's estate that the child would have received if the parent had died intestate.  However, this right is strictly limited to the property that is not given to the deceased parent's surviving spouse. The pretermitted child is also not automatically granted a share of the estate, but must properly contest the will first.

For Example:
Rob makes a will leaving all of his property to his wife, Julie, as the primary beneficiary, followed by their children, Joe and Missy, as alternate beneficiaries. Prior to his death, Rob and Julie have another child, Oliver, but Rob does not make a new will.

If Julie is living at the time of Rob's death she will receive all of Rob's property, because she is named as the sole primary beneficiary. Oliver is still a pretermitted child, but he does not have any rights to his father's property because it is all being given to a surviving spouse.

If Julie is not living at the time of Rob's death Oliver is entitled to receive one-third of the estate, which is the same amount he would have received if Rob did not have a will.  The shares of the other two children will be proportionately decreased by the amount required to pay Oliver's share. Each child will receive one-third of the estate, even though Rob's will gives Joe and Missy one-half each.

See: Children Born Out Of Wedlock; will Contests, Who May Contest; will Contests, Generally