The condrumn you found yourself in philosophy of antinatalism is the decision you may have made to spawn sentient entities, children, into this world without their anticipatory consent or agreeing to their existence in the world that you have brought them into and the household they won't or are being raised in. Under social contract theory, you are obligated to be a parent and protect your children and family from harm, while preserving and respecting their free agency and autonomy.
You cannot discharge or rescind your obligations by foreclosing their lives by force or compulsion against their will under the premise that you believe that they would be better off dead, because you no longer own their lives and cannot lay a claim on their lives in depriving them of their liberty in the pursuit of their happiness, peace or freedom.