Legal analysis: just to prove that the money was borrowed by parents, write "I borrowed XXXX yuan from my parents to buy a house today", and then the children (including spouse) sign and date it. If you are interested, then write clearly. If you want to pay back the money, write down the repayment date.

Legal basis: Civil Code of People's Republic of China (PRC).

Article 667 A loan contract is a contract in which the borrower borrows money from the lender, repays the loan at maturity and pays interest.

Article 668 A loan contract shall be in written form, unless otherwise agreed between natural persons.

The contents of a loan contract generally include terms such as loan type, currency, purpose, amount, interest rate, term and repayment method.

Article 669 When concluding a loan contract, the borrower shall, at the request of the lender, provide the true information about the business activities and financial status related to the loan.