P!nk's daughter, 7, now has purple hair. How safe is dye for kids?

P!nk’s 7-year-old daughter, Willow, is growing up to become a superstar in her own right. Since she was tiny, mom and dad Carey Hart have been open to sharing her journey to self-love — including, most recently, by posting a pic of her newly dyed hair, which was colored bright purple in honor of her birthday over the weekend. Hart shared photos, to the delight of fans, along with a celebratory message to his firstborn.

“Happy 7th birthday to my bad ass daughter Willow!!!!! I love this little girl more than life itself. She is becoming such a strong, smart, sensitive, little girl. I’m so proud of everything you are and I enjoy every moment we are together. Even when you are giving me a hard time! Happy 7th big girl, your mamma, little brother, and papa love you around the moon 10 million times and back,” he wrote. With another pic, he noted, “Have you med my daughter Wednesday Addams???”

Fans flooded the comment section with congratulations and admiration for Willow’s new look.

“Love the hair she is just so beautiful,” wrote one fan. Another noted, “When my daughter had purple hair her confidence really came out! She felt more herself! Love letting her show her independence!”

Willow is just the latest in what’s been a lasting trend of celebs’ kids experimenting with hair color. Recently, the son of Wiz Khalifa and Amber Rose, Sebastian, was photographed with a blond streak in his school photos.

Last year, beauty blogger Charity Grace LeBlanc came under fire after she shared a video with her 313,000 Instagram followers, in which she dyes her daughter’s hair pink.

But the naysayers did not stop LeBlanc from adding more hair dye to her little girl’s mane — not to mention a few longer extensions, for a full rainbow look.

So, how safe is hair dye when it comes to children?

Latanya T. Benjamin, MD, medical director of pediatric dermatology at Joe DiMaggio Children’s Hospital, doesn’t advise it. “There are many chemicals that a child could potentially absorb or have an adverse reaction to,” she told Yahoo Lifestyle in a previous interview.

One ingredient particularly worth being wary of is p-Phenylenediamine, an organic compound found in many hair dyes, also known as PPD. “PPD can trigger an allergic response to anyone at any time,” Benjamin explains. “A person can be sensitive to color at any point in life. Therefore, there is no safe age to start experimenting without prior patch testing to chemical ingredients.”

Colorist Maddison Cave of Rita Hazan Salon in New York City gives parents an alternative for a safer hair dyeing experience when it comes to children. She advises starting out with highlights or a sectioned pop of color on kids. “It’s a technique that doesn’t require color to touch the scalp,” she says. “Most color has ammonia or peroxide, so it is best to do color in the salon with good ventilation and off-the-scalp application.”

Semi-permanent colors, however (which could even be what Willow has on her locks), are also safe options, as they usually don’t contain ammonia — though the dye job won’t last as long. Although experts agree it’s always best to do a patch test before proceeding with hair coloring.

Would you ever consider dyeing your child’s hair? Let us know in the comments below!

Read more from Yahoo Lifestyle:

• This video of a 3-year-old girl with pink hair has the internet divided

• Picnic tablecloth-inspired dye job is wild and wonderful

• Your Hair Dye Is Killing You, According to This Advocacy Group

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