American Girl was girl power before girl power was cool. And this holiday season, the Mattel brand wants to remind people of that.

Mattel's brand juggernaut finally stumbled last year, according to Euromonitor, when American Girl sales fell for the first time since 2010. The company pegs the drop at 4% last year; sales also dipped 2% in the most recent third quarter from the same period a year earlier.

American Girl is pouring on a huge TV and social media push -- its largest ever, in an effort to drive the girl power conversation forward during the holidays. Tapping its own mission to "celebrate girls" along with the current girl power zeitgeist, American Girl is making the case that girls are even better together.

"This year is a more robust campaign centered on connecting girls with each other and with their families," said Julia Prohaska, senior director-global brand at American Girl. "You'll see more of our communications aligning with the belief that not only do our characters celebrate the strength of girls, and how that's led to the opportunities that girls have today, but also that contemporary real girls are stronger when they align and support one another."

A cornerstone of the campaign is a counter-culture social media push away from "selfies" to promote its new concept of "usies" instead. (American Girl defines a "usie" as picture that contains not just yourself but other friends.) American Girl and its agency Publicis, Seattle, are partnering with Maker Social, a new division of Disney's Maker Studio, and its teen influencers to create a movement around the hashtag #usies. The young influencers will use their social media channels to talk about usies, post them and try to move the conversation from selfies to recognizing the importance of the people who surround them.

More than 30 young social media influencers will participate, including college cheerleader Peyton Mabry, actor and dancer Chadd Smith who appeared in the "Step Up" movies, and another cheerleader well-known on social media, Carly Manning.

The usies will not be posted directly to American Girl nor will the brand be mentioned; however American Girl will re-post some of the usies to its Instagram account and other social media through the holidays, said Britt Fero, head of strategy at Publicis Seattle.

"American Girl wants to create and champion the cultural term and idea of 'usies' that in a lot of ways 'we' is better than 'I.' "she said. "As all these brands have helped girls see the strength they have inside of themselves, which is great and important, we also want them to see the strength they have in each other. … That sense of belonging and connection is something we're seeing girls need now more than ever."

Three TV spots, tagged "Together We Make the Holidays" and also created by Publicis, will continue the better together theme. The first, already running, highlights a promotion in which American Girl will donate a doll to a girl in need for every one purchased. The "Buy One, Give One" program, in conjunction with the Children's Hospital Association, runs through the end of month and includes integrations on TV shows NBC "Today" and CBS' "The Talk." A second TV spot shows a young girl who receives a doll from her elderly neighbor who then brings a group of friends to help the neighbor decorate for the holidays in appreciation of the "friend" she was given.

The third TV spot set for December run takes a lighthearted "12 Days of Christmas" approach weaving several American girl products into the traditional song, marking the first time the brand has advertised products beyond dolls. The spot will also include a new co-created William-Sonoma collection, beauty and craft products and books.

The overall U.S. toy industry is set for a booming year with an expected $19 billion-plus in revenue, an increase of 6.2% for 2015, according to The NPD Group.

"I can't say for sure that girls are playing with the dolls, but their parents are definitely buying a lot of them," said Juli Linnett, senior VP of The NPD Group's toy division. "Dolls are one of the most classic play patterns for girls … and there's no substitution for that. You can't get that from electronics or on the computer."

NPD does not track American Girl doll sales as it reports separately from Mattel. But according to Euromonitor (see chart, below) American Girl was the 7th most popular brand in North American traditional toys and games (not including video games) last year with sales of $346 million. The only higher ranking doll brand was Barbie, also Mattel-owned, at No. 4 and $598 million in sales.

Also working in American Girl's favor is that as it celebrates its 30th anniversary next year -- it's selling to a new generation of mothers who had American Girl dolls when they were young.

"The first generation of girls who played with American Girls are becoming moms and they are reaching back to the brand now for their daughters," Ms. Prohaska said. "Part of this idea of banding together isn't just about one 9-year-old with another 9-year-old, it also celebrates the relationship that girls have with their moms and that moms have with their friends and then that connection that they mutually have back to the brand."