A more thorough explanation:

Definition: A sibling is a brother or sister.

Examples:

• My younger sister is my sibling.
• He has two older brothers, making him the youngest sibling.
• She and her brother are very close, they have a strong sibling bond.

The examples illustrate that a sibling is a family member who shares the same parents or one parent with another person. It can be a brother or a sister, and the relationship between siblings can vary from being close and supportive to distant and strained.