Haim (band) spotted by musician Jenny Lewis at a jam session in Laurel Canyon, which led to Danielle joining Lewis' touring band. The Strokes' singer Julian Casablancas came to see one of Lewis's shows on tour, and he in turn asked Danielle to play guitar and percussion on his solo tour. Danielle rehearsed with Casablancas' band every day for two months, which she later described as "an eye-opening experience." Following working with Casablancas from late 2009 to mid 2010, she auditioned for a place in Scarlet Fever, the all-female backing band for CeeLo Green. Danielle performed only once with the group, on
Julian Casablancas and Sparklehorse on the song "Little Girl" on the 2010 album, "Dark Night of the Soul", contributing the lyrics, lead and backing vocals, and guitar solo. Aside from vocal collaborations, he also contributed to a song, "Forrest Gump", on Digitalism's sophomore album "I Love You, Dude" in 2011. The electronica duo initiated a collaboration with Casablancas through his manager, and Casablancas contributed 'a 30-second recording with him on guitar' via email. Casablancas also lent his vocals to the title track, "Rave On", on a 2011 tribute album to Buddy Holly, "Rave On Buddy Holly". In 2016, Casablancas contributed three specially