Reference for Bava Batra 286:6

אמר אביי ת"ש (בראשית מו, כג) ובני דן חושים א"ל רבא דלמא כדתנא דבי חזקיה שהיו מרובין כחושים של קנה אלא אמר רבא (במדבר כו, ח) ובני פלוא אליאב רב יוסף אמר (דברי הימים א ב, ח) ובני איתן עזריה

or not? — R. Habiba said: People call a grandson 'son'.<span class="x" onmousemove="('comment',' Hence the estate would he divided between the son and the grandson. ');">¹⁸</span> Mar son of R. Ashi said: People do not call a grandson. 'son'<span class="x" onmousemove="('comment',' And the whole estate would consequently be given to the son who, as mentioned above, might be called 'sons'. ');">¹⁹</span> [A Baraitha] was taught in agreement with the view of Mar son of R. Ashi: He who is forbidden by a vow [to have any benefit] from [his] sons is allowed [to derive benefits] from [his grandsons].<span class="x" onmousemove="('comment',' Which proves that grandsons are not regarded as sons. ');">²⁰</span> <b><i>MISHNAH</i></b>. HAD ONE LEFT SONS [WHO WERE] OF AGE AND MINORS, [AND] THOSE [WHO WERE] OF AGE IMPROVED THE ESTATE,<span class="x" onmousemove="('comment',' Before it was divided between the heirs. ');">²¹</span>

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