Mia Sinclair Jenness stars in the title role of the series, an adaptation of the best-selling kids' books.

Alyson Hannigan and Rob Riggle have signed on to voice roles in Disney Junior's upcoming animated series Fancy Nancy.

Hannigan (How I Met Your Mother) and Riggle (Modern Family) star as Nancy's parents, Claire and Doug Clancy.

Mia Sinclair Jenness, a 12-year-old Broadway actress who starred in Matilda, will voice the title role of Nancy, a lovable young girl whose zest and enthusiasm for all that is fantastic transforms the ordinary into the extraordinary.

Newcomer Spencer Moss voices Nancy's younger sister, Jo Jo, in the show, which is set to premiere this summer on Disney Junior and the new DisneyNOW app.

Based on the New York Times best-selling books by Jane O'Connor and Robin Preiss Glasser, the animated family comedy centers on 6-year-old Nancy, a girl who likes to be fancy in everything from her advanced vocabulary to her creative, elaborate attire. Excited to experience what the magnificent world has to offer, Nancy uses her ingenuity and imagination as she learns that while life doesn't always go as planned, it's important to celebrate the differences that make everyone unique.

Each episode of the show, aimed at kids ages 2-7, contains humorous and heartfelt stories that highlight themes of self-expression, originality and love of family.

Disney Consumer Products and Interactive Media also is set to launch a line of products, including dolls, role-play items, accessories and apparel, which will be revealed at the New York Toy Fair this weekend.

The Fancy Nancy book series includes more than 100 titles, with more than 30 million books sold, that have been translated into 20 languages.

Disney Junior is a daily programming block on Disney Channel and a 24-hour channel targeting kids 2-7.