lululemon may not have a significant men's presence to compete with Under Armour and Nike, but its ivivva girls' stores are performing well,

Lululemon's ivivva athletica store in Edmonton, Canada. Image source: lululemon.

It seems an understatement to say shareholders of lululemon athletica (LULU 1.31%) had a rough year in 2013.

Even as the market's broader indexes roared to new all-time highs, Lululemon stock fell by around 20% last year thanks to the extended fallout from a massive recall in March, an unexpected resignation announcement by its CEO in June, and some less-than-savory comments from founder Chip Wilson in November.

But now things are looking up for the yoga apparel specialist, which not only just hired a promising new CEO last month, but is also working to streamline its supply chain going forward.

What's more, notes the Fool's Steve Symington in the following video, Lululemon still managed to grow its top line by 20% year over year last quarter thanks to a combination of strong e-commerce sales, new locations, and decent 5% comparable-store sales growth.

Best of all, Steve says, somewhat hidden in Lululemon's results was the outstanding performance of its new "little sister" brand, ivivva athletica, which focuses on activewear for girls. Specifically, ivivva outlets achieved solid 17% comparable-store sales growth in Q3, which is why Lululemon is planning on increasing the brand's new location roll-out in the coming year.

To get Steve's full take on how ivivva could prove to be Lululemon's next big growth driver, check out the video below.