Enjoy a musical experience, from the pages of Mo Willems’ beloved, award-winning, best-selling children’s books. In Elephant & Piggie’s “We Are in a Play!”, an elephant named Gerald and a pig named Piggie are best, best, “bestus” friends, but Gerald worries that something could go wrong that would end their friendship. Piggie is not worried at all. She’s even happier and more excited than usual. That’s because she and Gerald are invited to a party hosted by the Squirrelles, three singing squirrels who love to have a good time. And so begins a day when anything is possible. Tickets are $12 and on sale at nbparks.org, starting August 1.