Welcome to Billboard Pro’s Trending Up newsletter, a weekly dive into the songs, artists, curiosities, and trends capturing the music industry’s attention. This edition explores a posthumous surge in catalog interest for a rock legend, a Latin superstar sparking a viral hit, and a '90s karaoke staple experiencing a remarkable resurgence on social media platforms.

The music world mourned the passing of Ace Frehley, the iconic lead guitarist and occasional singer for rock legends KISS, on Thursday, October 16. Frehley, affectionately known as "The Spaceman" or "Space Ace," died at age 74 following a brain bleed caused by a fall. A Rock and Roll Hall of Famer, he was celebrated as one of his generation's greatest guitarists and showmen.

In the three days following Frehley’s death (October 17–19), his legacy saw a significant renewal of interest. The KISS back catalog amassed nearly 6.8 million official on-demand U.S. streams, representing a substantial 187% gain from the preceding three-day period (October 13–15), according to Luminate data. Digital song sales for KISS also surged, rising 1,664% to nearly 4,500 units. A standout performer was the 1978 Billboard Hot 100 No. 13 hit “New York Groove,” which, although a solo chart credit for Frehley, is attributed to KISS in Luminate. “New York Groove” recorded 318,000 streams and sold over 700 copies during this period, marking gains of 530% and 4,217%, respectively. Frehley’s solo catalog also experienced a notable spike, collecting 586,000 streams and nearly 800 songs sold, gains of 2,940% and 5,140%.

Meanwhile, Latin superstar Karol G ignited viral interest in her song “Ivonny Bonita” from the Tropicoqueta album following her performance at the 2025 Victoria’s Secret Fashion Show on October 15. The track, already a popular sound among the TikTok edit community, saw streaming figures soar after the sultry performance. In the four days following the show (October 17–20), “Ivonny Bonita” surged 204% in streaming activity, reaching 1.11 million official on-demand U.S. streams, up from 366,000 streams in the preceding four days (October 10–13). The official YouTube upload of Karol G’s performance garnered over 1.1 million views in just four days. Karol G is also a leading female nominee for the 2025 Billboard Latin Music Awards, airing live from Miami, Florida, on October 23.

Finally, 4 Non Blondes’ 1992 alt-rock power ballad “What’s Up?” continues to prove its enduring appeal, demonstrating as much cultural relevance in 2025 as ever. A No. 14 Hot 100 hit in 1993, the song recently saw a renewed surge in popularity. In September, it was heavily interpolated by Lizzo for the hook of Cardi B’s Am I the Drama? More recently, the track exploded on TikTok as part of a mashup with Nicki Minaj’s “Beez in the Trap,” becoming so viral that SNL cast member Marcello Hernandez and host Sabrina Carpenter featured it in a promotional video. This enduring relevance has pushed its already strong streaming numbers even higher. Last tracking week (October 10–16), “What’s Up?” garnered 2.6 million streams, an 11% increase from the prior week. It continued its hot streak into the current tracking week, accumulating 901,000 streams in its first two days (October 17–18), a 20% jump from the same period last week.