Illegal.
 It is the duty of parents to raise their children. Divorce of parents only relieves the marriage relationship of both parties, but not the responsibility of parents to raise their children. If one party is really unable to support the child due to living difficulties, it can ask the party who is able to support the child to increase the alimony or change the right to support the child. If the party who does not directly support the child refuses to pay the alimony or refuses to increase the alimony without justified reasons, the minor child can file a lawsuit to the people's court to ask it to pay or increase the alimony. If the other party still refuses to pay, Can apply to the court for enforcement.
 Therefore, it is illegal for parents to divorce regardless of their children.
 [Legal Basis]
 According to Article 1084 of the Civil Code, after divorce, parents still have the right and obligation to support, educate and protect their children.
 (The effective date of the Civil Code is January 1, 2021)