Jennifer Lopez celebrated a very special quinceañera, her fiancé Alex Rodriguez's daughter Natasha, by wishing her soon-to-be stepdaughter a happy birthday on social media. The Hustlers star took the opportunity to send the special message to "her favorite teenager", who is affectionately called Tashi, sharing a sweet photo of the two hugging each other during the 15-year-old's birthday party. Among the guests at the bash were Jennifer's 11-year-old twins with Marc Anthony, Emme and Max, as well as Tashi's mom, A-Rod's ex-wife Cynthia Scurtis.

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©@JLo

In the photo she posted, JLo gave us an inside look at details of the party, including the two-tiered birthday cake, bedecked with flowers and pink frosted donuts with sprinkles. Alongside the sweet photo, she wrote: "Wishing my favorite teenager a very happy 15th birthday!!! May you forever keep illuminating the people around you with your infectious light. I love you and hope you have the best day. #Tashi."

©@JLo

Alex opened up his heart to send Tashi his own special message on social media. Alongside a photo of father and daughter together at the birthday party, he wrote: "To my beautiful, amazing daughter… I can’t believe how old you are now and how much you’ve grown. I am so proud of the girl you’ve become and continue to be each day. I am so lucky to have you as my daughter and so honored to be your dad. Happy Birthday, Tashi!!! I love you so much!!!!" His future bride Jennifer couldn't resist commenting, posting: "Sooooo sweet!!"

Alex also gave us a peek inside Tashi's family life, sharing an emotional 2-minute video showing their sweetest moments together. The video, set to songs including Coldplay's Yellow, Journey's Don't Stop Believin', and JLo's On the Floor, features cameos by both Jennifer and Cynthia, as well as footage of Tashi dancing in the audience with her dad during one of Jennifer's concerts.