Is feeding a non-Muslim child non-halal meat by a nanny sinful, knowing that feeding the child is her duty?

It is not permissible to offer forbidden food to children, because it is assisting in sin, and because non-Muslims are bound by the branches of Islamic law, so it is not permissible for them to eat what is unlawful. Similarly, a child must be prevented from eating what is unlawful, just as the Prophet, peace and blessings be upon him, prevented Al-Hasan from eating a date from the dates of charity. Therefore, one must refrain from offering forbidden food and be keen on earning a lawful livelihood. Families can be dealt with on the basis of them bearing the cost of feeding their children in exchange for fees, or by limiting services to Muslim children only.