Reference for Bava Batra 281:10

והא דתניא ילדה זכר ונקבה אין לו אלא מנה היכי משכחת לה אמר רבינא במבשרני

The other <i>maneh</i> [however] is money of doubtful ownership<span class="x" onmousemove="('comment',' Because it is not known to whom that second maneh belongs. Had it been certain that the son was born first he would have been entitled to that maneh also. Had it been certain, on the other hand, that the daughter was born first she would have been entitled to that maneh; hence it is of doubtful ownership. ');">³⁵</span> and is to be divided.<span class="x" onmousemove="('comment',' Between the son and the daughter. The first maneh being due to the son in any case, is given to him in full (four gold denarii), with the addition of a half (two gold denarii) of the second maneh. Hence he receives a total of one maneh and a half (six gold denarii). The daughter, being entitled to half a maneh, receives, therefore, two gold denarii. ');">³⁶</span> And how is one to understand the Baraitha which teaches<span class="x" onmousemove="('comment',' Lit., 'but that which was taught … how do you find it'. ');">³⁷</span> [that 'if] she gave birth to a male and a female, he only receives one <i>maneh</i><span class="x" onmousemove="('comment',' The expression 'he only receives one maneh', implies that though it might have been assumed that he receives more than that sum, he receives only one maneh. Under what circumstances is this possible? ');">³⁸</span> — Rabina replied: [This is possible] where [the promise of the sum of money was made by the father]. 'to him who will bring me tidings';<span class="x" onmousemove="('comment',' Whether the child born was male or female. ');">³⁹</span>

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