On their current “50 And Counting” arena tour, the Rolling Stone have regularly been welcoming guests, including Tom Waits, to their stage. And when they played in Arcade Fire’s hometown of Montreal over the weekend, Arcade Fire frontman (and new dad) Win Butler joined them to sing and play guitar on the Stones’ 1965 single “The Last Time.” Butler wore blinding white, towered over the entire band, and generally came off like someone who belonged on that stage. Watch a fan-made video below.

Babies take a whole shitload of attention, so this could be the last time we see Butler onstage for a while. Baby, I don’t know. Enjoy it.