'I can't tell you how proud I am,' Paris sweetly wrote alongside the cute snap.
Happy birthday, Blanket!
Michael Jackson's youngest child turned 15 years old on Tuesday, and his big sister, Paris Jackson, couldn't help but celebrate with the greatest throwback pic, along with a sweet message to her little brother.
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"Ughhhhhh my little man is 15 today. slow the f**k down, i want you to stay a baby forever ???," Paris wrote. "This lil dude right here is one of the most strong, intelligent, and determined people i know. Watching you grow up and slowly become a man is like super terrifying but i honestly can't tell you how proud i am."
"i love you so much B," she concluded her message.
Paris clearly has a lot of love for her brothers. Just last week, the rising model posted an adorable pic of herself and her older brother, Prince, in honor of his 20th birthday.
"The coolest big brother ever and my bestest friend in the whole wide world is 20 today and i honestly can't believe how fast the time has gone by," Paris, 18, captioned the snap. "Thank you gooko for always supporting me and encouraging me to be myself. there's no one like you, you're my rock. happy birthday, i love you."
Paris has continued to stay close to her mother, Debbie Rowe, as well, recently revealing that she and Rowe have decided to get matching tattoos.
Find out more on the mother-daughter ink in the video below.