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Keira, wearing one of the shirts her dad created for his new company Keira's Kollection. (Photo: Kevin Wagstaf …After reading about a girls' T-Shirt printed with "I'm Too Pretty to Do My Homework so My Brother Has to Do It For Me," Kevin Wagstaff was appalled. But instead of venting to his friends or vowing not to buy the shirt, the single dad decided to do something about it.

"Seeing that shirt kind of was just like, 'Boom! Light bulb moment'," Wagstaff, who has a 6-year-old daughter, told Yahoo! Shine in an interview. "I rolled my eyes and thought, 'This is a problem that's snowballing in the wrong direction'. I thought to myself, 'If someone can approve this, to put this out, they must feel like there's a market for it.' So I'm thinking that I want to create a market that's the inverse of that."

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A year later, he's launched his own company, selling T-shirts that encourage, support, and inspire girls to be their best selves. The shirts at Keira's Kollection, which is named after his daughter, are stamped with messages that any parent would be proud to see their child wear.

Kevin Wagstaff and his daughter, Keira. (Photo: Kevin Wagstaff/KeirasKollection.com)"Be Confident. Be Different. Be Yourself," one shirt declares. On another, adorned with the flowers and butterflies that little girls love, features 10 key attributes that we all want for our kids. The words -- like "positive," "loving," "healthy," "creative," "adventurous," and "independent" -- form the figure of a pony-tailed girl standing confidently with her hands on her hips. It's the logo for Keira's Kollection.

The Denver-based dad says that he was aiming to create "that positive charge that I think young girls need." And his daughter loves the shirts.

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When Keira saw the final product, "I explained to her that I want all these things for her, and that I want these things for all girls and women," Wagstaff says. "She was like, "Yeah, that makes sense'."

"She loves the one with the flowers and butterflies on it," he says. It's girly and strong at the same time, so girls know that they don't have to choose between pretty and powerful. "There's a proper way to mix these things together," he explains.

The 100-percent cotton shirts are designed by his brother, graphic designer and digital media consultant Michael Wagstaff. They range in price from $12 to $20, and come in sizes and styles for toddlers, girls, and women.

"Girls emulate what their parents do and what older girls do," Kevin Wagstaff points out. "It's been good to see some of my adult female friends embrace the shirts."

He hopes to eventually partner with a charitable organization that helps girls and promotes good self-esteem.

"I do want to make a real-world difference with this," he told Yahoo! Shine. "There's always room for another brand that can do good, that can push against the avalanche of media or bad advertising."