Is it permissible to make the partner's share in the Udhiyah (sacrificial animal), a calf, equivalent to a second sheep for the 'Aqiqah?

The 'Aqiqah is not obligatory, according to the consensus of the four madhhabs (schools of thought). The Malikis held that it does not multiply, and one sheep suffices for each newborn, as it was narrated that the Prophet (peace be upon him) sacrificed one ram for Hasan and one ram for Husayn. While the Shafi'is and Hanbalis held that it is recommended to sacrifice two sheep for a male and one sheep for a female, based on the Prophet's (peace be upon him) saying: "For a boy, two equivalent sheep, and for a girl, one sheep." It is preferable to slaughter two sheep for a boy if possible, and there is no harm if they are separated. It is permissible to suffice with one or to combine the Udhiyah (sacrifice of Eid al-Adha) and the 'Aqiqah if unable to offer two sheep.