18th and 21st birthdays are milestones in your teenagers' development, the universally acknowledged age at which true adulthood begins. They're a symbolic way of letting go, and you'll want to celebrate in style.

For a complete guide to the various ways in which you can celebrate these landmark birthdays, click the link below:

See Rites of Passage: 18th and 21sts

See Miss Debrett on Becoming an Adult

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