We haven't seen much of Neil Patrick Harris' twins Harper and Gideon, but on his Thursday appearance on "Late Night with David Letterman," he fixed that. The "How I Met Your Mother" star revealed that he and partner David Burtka dress the kids in costumes for a monthly photo shoot. "We do one a month," he said. "We're doing a calendar, so that when they're older, we can humiliate them and embarrass them."
Watch the above clip -- a favorite pic you'll see toward the end: May's Cinco de Mayo-themed shoot that features Gideon in a sombrero, and Harper paying homage to Frida Kahlo, complete with unibrow.
