Mental health is highlighted in Selena Gomez's 31st birthday message: My life's work.

Selena Gomez celebrates 31st birthday, thanks fans on social media.

She sports a pink shirt, pearl necklace, and flowing brown hair.

Gomez blows out candles on an S-shaped chocolate cake with flowers.

Her Instagram post highlights Rare Beauty cosmetics and her mission to help others.

She's grateful for the Rare Impact Fund's work in raising mental health awareness.

The Disney alum is passionate about increasing access to mental health services.

Selena expresses her true passion for helping young people through her work.

Selena Gomez celebrates 31st birthday, thanks fans on social media.

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