As legal heirs, children can't be witnesses to the will, so they can't help their parents write the will. However, if the children are excluded from the scope of heirs in the will, and the children have no interest relationship with other heirs, they can write a will on their behalf. A will that entrusts others to write on behalf of others shall be witnessed by two or more witnesses, and one of them shall write on behalf of others, which shall be signed by the testator, agent and other witnesses, and marked with the year, month and day.

legal ground

Article 135 of the Civil Code of People's Republic of China (PRC)

A will that entrusts others to write on behalf of others shall be witnessed by two or more witnesses, and one of them shall write on behalf of others, which shall be signed by the testator, agent and other witnesses, and marked with the year, month and day.

Article 143

A will made by a person without or with limited capacity for civil conduct is invalid.

A will must express the true meaning of the testator, and a will made by fraud or coercion is invalid.

Forged wills are invalid.

If the will is tampered with, the tampered contents are invalid.

Article 139

A notarized will shall be handled by the testator through a notarization institution.