If the elder sister gives the house property before the younger brother's marriage, it is the personal property of the younger brother before marriage.
If the elder sister gives the property to the younger brother after marriage, the married couple will share the property together unless it is specially agreed that the younger brother will give it to them personally when giving the property.
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Relevant laws and regulations
Article 1062 of the Civil Code: The following property acquired by husband and wife during the marriage relationship is the common property of husband and wife and belongs to both husband and wife:
(1) Wages, bonuses and remuneration for labor services;
(2) Income from production, operation and investment;
(3) Income from intellectual property rights;
(4) Inherited or donated property, except as provided for in Item 3 of Article 1063 of this Law;
(five) other property that should be owned by * * *.
Husband and wife have equal rights to dispose of the same property.
Article 1063 of the Civil Code: The following property is the personal property of one spouse:
(1) one party's premarital property;
(2) Compensation or compensation obtained by one party for personal injury;
(3) Property that is determined to belong to only one party in the will or gift contract;
(4) Daily necessities used exclusively by one party;
(five) other property that should be owned by one party.