Reference for Bava Batra 318:8
אמר ליה רב אחא בר מניומי לאביי אף אנן נמי תנינא נפל הבית עליו ועל אמו אלו ואלו מודים שיחלוקו ואם איתא נהי נמי דבן מת ברישא לירתיה לאמיה בקבריה ולירתו אינהו לאחי מאבוה אלא לאו שמע מינה אין הבן יורש את אמו בקבר להנחיל לאחין מן האב שמע מינה
— R. Shesheth said to them, You have learnt it: If a father was taken captive [and died] and his son died in the [home] country, or if a son was carried into captivity [where he died] and his father died in the [home] country. [the estate] is to be divided between the heirs of the father and the heirs of the son. How is this to be understood? If it be suggested [that it is to be understood] as was taught,<span class="x" onmousemove="('comment',' That it is a case of a father and his own son, ');"><sup>14</sup></span> who then are the heirs of the father and who are the heirs of the son?<span class="x" onmousemove="('comment',' Both, surely. are represented by the very same heir or heirs. If the son has no issue the heirs of the father would also inherit the sons' estate, and if he has issue, his sons would inherit the estate of their grandfather as well as that of their father. ');"><sup>15</sup></span>