This is a question of alimony. If the two parties divorced by agreement and agreed on the amount of alimony, you can take this to the court to file a lawsuit and ask the other party to pay the living expenses of the child. If you divorce by litigation and the original judgment or mediation of the amount of alimony, you can directly take this effective document to the court to enforce and urge the other party to perform its obligations.
 Marriage Law of the People's Republic of China
 ‖ Article 37 After divorce, for the children raised by one party, the other party shall bear part or all of the necessary living and education expenses. The amount and duration of the expenses shall be agreed by both parties; If the agreement fails, the people's court shall make a judgment.
 The agreement or judgment on children's living expenses and education expenses shall not prevent children from making reasonable demands to either parent in excess of the original amount of the agreement or judgment when necessary.
 ‖ Several Specific Opinions of the Supreme People's Court on the People's Court's Handling of Divorce Cases and Child Support
 Article 7 The amount of childcare fees can be determined according to the actual needs of the children, the affordability of both parents and the actual local living standard.
 ‖ If there is a fixed income, childcare fees can generally be paid at the rate of 20% to 30% of the total monthly income. The proportion of those who pay for the upbringing of two or more children may be appropriately increased, but generally shall not exceed 50% of the total monthly income.
 ‖ If there is no fixed income, the amount of childcare fees can be determined according to the total income of the year or the average income of the same industry, with reference to the above proportion.
 ‖ In case of special circumstances, the above proportion can be appropriately increased or reduced.
 Marriage Law of the People's Republic of China
 Article 37 After divorce, for a child supported by one party, the other party shall bear part or all of the necessary living and educational expenses. The number of expenses to be borne and the length of the period shall be agreed upon by both parties; If the agreement fails, the people's court shall make a judgment. The agreement or judgment on the children's living expenses and education expenses shall not prevent the children from making reasonable demands to either of the parents in excess of the original amount of the agreement or judgment when necessary.
 Article 48 If a person refuses to enforce a judgment or ruling on alimony, upbringing, alimony, property division, inheritance, or visiting children, the people's court shall enforce it according to law. Relevant individuals and units shall be responsible for assisting in the implementation.
 Article 49 Where other laws provide otherwise for illegal acts and legal liabilities related to marriage and family, such provisions shall prevail.