Is celebrating the Subu' (seventh day after birth) forbidden, and am I sinful if my family celebrates it despite my advice to them, and what should I do in that situation?

The Sunnah for a newborn is to have an aqiqah performed for them on the seventh day, with two sheep for a boy and one sheep for a girl. The child is also named, their head is shaved, and silver equivalent to the weight of their hair is given in charity. As for the "Subu" ceremony as it is known today, it involves innovations (bidah) and deviant beliefs, such as sprinkling salt, pounding the mortar, lighting candles, and that tray containing seven grains of rice, beans, and lentils for good fortune, and the censer which the mother steps over seven times. All of this is extravagance and wastefulness that is impermissible to perform or assist with. However, merely distributing sweets and gifts and the presence of children is permissible, as long as it is not linked to a corrupt belief or includes something forbidden. The believer should be keen on adhering to the Sunnah and avoiding innovations.