Is it permissible to share in one cow with the intention of sacrificing it as a vow and for the 'aqiqah of a newborn girl?

The participation of two individuals in sacrificing a cow on behalf of two vowed sheep is a matter of scholarly disagreement. The Shāfi‘īs permit this, holding that a cow suffices for seven individuals, whether the sacrifice is for 'īd al-aḍḥā (the festival of sacrifice) or for meat, and whether it is voluntary or a vowed offering. In contrast, the Ḥanafīs and Mālikīs believe it is obligatory to fulfill a vow exactly as specified, and it is not permissible to deviate from it except in cases of inability. As a precautionary measure, it is preferable for each of them to sacrifice a sheep to avoid the disagreement. As for the 'aqīqah (sacrifice for a newborn), shared participation is not permissible.