SXSW ROCKS ON: First there was She and Him. Now there’s He’s My Brother She’s My Sister, the hipster band fronted by siblings Rachel and Rob Kolar along with tap-dancing drummer Lauren Brown, green-haired Oliver Newell and slide guitarist Aaron Robinson. The band took the stage Wednesday at Sonos Studio at the South by Southwest Festival in Austin, after which they chatted with WWD.

“It’s almost like yin and yang,” she explained of their dynamic.

And while her brother has been dating Brown, whom she met in drama school at New York University, the group somehow finds a way to keep the theatrics confined to the stage. “It teaches you patience,” Brown noted of working with her partner of seven years. “And when we have these sold-out shows I get to have that awesome moment with the people that I love.”

Their differing fashion styles meld easily as well. “Once I discovered the onesie, I was like, ‘Oh, I can have tons of these [for the road],” joked Rachel Kolar of her zebra print unitard. “It opened up a portal,” teased Brown, whose Mod look is decidedly tamer. “Rachel is ever-evolving. She’s constantly changing your look like Madonna, and I like it because it forces the band to move with it. I still want to look like I’m friends with the person who wears this, and she’s a risk-taker,” said Brown, clad in a vintage top and striped Paige pants. The band can’t wait to take in the music fest’s other acts in between their own back-to-back performances over the next couple of days, citing Foxygen, Jazz Mills, and Esmé Patterson as must-see bands.

Later that night, members of Surfer Blood, who rocked out at Sonos Studio earlier in the week, kicked back at the after-party for Jared Leto’s documentary “Artifact,” which chronicles the making of 30 Seconds to Mars album, “This is War” and the band’s battle against record label EMI. Leto paired a Burberry trench with a t-shirt featuring his director pseudonym, Bartholomew Cubbins, named after a Dr. Seuss character.

“When I first started directing about ten years ago, I started using it for fun and for freedom,” Leto explained of the inside joke tee, which he sells on his Web site “You have to be entrepreneurial in this business,” noted Leto, whose new single with 30 Seconds to Mars, “Up in the Air,” will be released on March 18.

Leto has somehow hit on the festival’s trifecta, seamlessly bringing together his interactive, music and film interests, even speaking on a panel earlier in the day about his latest tech venture, VyRT, which streams live music performances. And after returning from a five-year break from acting with a role as a transsexual in “Dallas Buyers Club,” he has never seemed happier. “Thanks for noticing. I am really grateful,” he said, attributing his current state of mind to “getting older.” It can’t hurt that his documentary has been getting kudos, too. He celebrated with pal Balthazar Getty, Kenna, and producer Emma Ludbrook at Swift’s Attic, where a DJ spun everything from Tina Turner to Notorious B.I.G.