Yes, in India, a person can generally leave their property to only one child through a valid will, but the answer depends on the nature of the property.
If the property is self-acquired property, the owner generally has the freedom to leave it to one child and exclude other children from the will. The will should clearly identify the beneficiary and the property being transferred.
However, ancestral or joint Hindu family property can involve different rules. A person may not have the same freedom to dispose of the entire property because other coparceners may have legal rights in it.
To reduce the possibility of disputes, the will should be properly drafted, clearly state the testator's intentions, identify the assets and beneficiary, and comply with the applicable legal requirements. Registration of a will is generally not compulsory, although proper execution and witnessing are important for its validity.
If a family member believes that the will was made under fraud, coercion, undue influence, or when the person lacked testamentary capacity, the will may be challenged in court.