Reference for Yevamot 47:18

כבכור מה בכור בכורתו גרמה לו אף גדול גדולתו גרמה לו

is entitled to the privilege,<span class="x" onmousemove="('comment',' Of the levirate marriage. ');">⁴⁴</span> but that where there is a firstborn the younger brother, even if he forestalled him, is not entitled to the privilege? — Scrip. stated, If brethren dwell together,<span class="x" onmousemove="('comment',' Deut. XXV. 5. ');">⁴⁵</span> the dwelling of one brother was compared to that of the other.<span class="x" onmousemove="('comment',' All brothers must be equal in respect of the levirate marriage. ');">⁴⁶</span>

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