The 30-year-old actress and musician had her TikTok followers melting after she posted a throwback video of herself singing with her little sister Gracie Elliot Teefey at an Olivia Rodrigo concert.  The adorable video, posted on Friday, August 19, featured Gomez and Teefey singing along to Rodrigo’s smash hit “drivers license” while attending the Sour Tour. The Only Murders in the Building actress appeared to be wearing a Sour Tour bucket hat while bending down to sing the lyrics with her little sis.  “And I just can’t imagine how you could be so okay now that I’m gone,” the sister duo sang to each other, with Gomez lovingly tapping the 9-year-old on the nose before they both leaned in for a sweet hug at the end of the video.  Gomez’s fans on TikTok almost couldn’t handle the cuteness.  “I love everything about this video I can’t 😭🥹,” one wrote. “Something about Selena singing with her little sister at an Olivia Rodrigo concert healed my inner child,” someone else commented, while another chimed in to call Gomez “one of the sweetest celebrities out there.”  The wholesome sisters weren’t at the concert alone, though; Jessica Simpson had previously revealed that her 10-year-old daughter Maxwell was also in attendance.  “She went with Selena,” Simpson revealed in an Instagram live, per E! News. “She met a really good friend of Selena’s little sister, so Max got to go to her first concert.”  Simpson, 42, thanked the Rare beauty mogul for being such a good babysitter.  The “Lose You to Love Me” singer is known to serve as an amazing role model for Teefey, who Gomez’s mom, Mandy Teefey, shares with Brian Teefey.  Back in 2017, the songstress made a heartfelt Instagram post promising to always empower her younger sibling. “I will forever let my sister know she is strong, bold and beautiful. She will be raised to know her voice matters. She is going to understand the importance behind being a leader and inspire others by her truth,” Gomez wrote at the time.  “I wish she was my sister,” someone commented on the 2017 post. And come on—who wouldn’t?  More News: • Martin Short Jokes About Competing With ‘Only Murders in the Building’ Costar Steve Martin For Emmy • Gary Busey Arrested in New Jersey, Charged With Sex Crimes • Chipotle Calls Out Drink Thieves With Lemonade-Scented Candle in a Water Cup