Gift to children dying to take effect per stirpes

Where any such person, being a child or other issue of the testator, to whom any real or personal estate is devised or bequeathed for any estate or interest not determinable at or before the death of such person dies in the lifetime of the testator leaving issue, and any such issue of such person is living at the time of the death of the testator, such devise or bequest shall not lapse, but shall take effect as if the death of such person had happened immediately after the death of the testator, unless a contrary intention appears by the will.