A two-year-old with a prominent birthmark on her face has used her first day at preschool as an opportunity to teach peers about her unique condition.

In a post to Love What Matters Facebook page yesterday, Colorado-based mother Kelly Wilson Bossley described how daughter Lydia, who has a port-wine stain on her face, reacted to discovering her new classmates “staring and whispering” at her face.

Lydia was left bruised from a treatment aimed at reducing the birthmark.

Ms Bossley said rather than getting upset, Lydia fetched a copy of a children’s book on the subject, Sam’s Birthmark, and handed it to her teacher so she could read it to the class.

“She isn’t even three yet but her resilience and ability to self-care blows me away,” Ms Bossley wrote.

Ms Bossley said she was so proud of her daughter’s action she was reduced to tears.

Her post, which has drawn tens of thousands of reactions, has even received comment from the author of Sam’s Birthmark, Martha Wardlaw Griffin.

Port-wine stain birthmarks are the result of a vascular malformation in the skin. If left untreated, the mark can spread, leading to loss of function in affected areas and bleeding.

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