Is it permissible to celebrate birthdays with an apostate father in order to obtain money and send it to a needy mother?

What we advise you to do is to strive to bring your father back to the religion of Islam with kindness, to treat him well, to be patient with his harm, and to advise him gently, while hating his state of disbelief and disobedience, and separating from him when he commits disobedience. It is not permissible to participate with him in celebrating New Year's, as it is a festival of the disbelievers, and your participation in this evil is not permissible, even if it is to obtain money for your mother. It is better for you to look for work to provide for your mother and become financially independent.