"It did take some effort to find something that I didn't feel was sort of sexy witch," recalled the Toronto-based writer and author who blogs at her website Embrace the Chaos and for Today's Parent.
Waverman said some of the witch costumes featured laceup corsets, and has remembered seeing other getups featuring skirts that are "quite short."
"It definitely can veer into trampy Halloween if you're not careful about it. I don't think that girls see it that way, but for some reason costumes definitely can be a little bit just more sexy or sexified than I would choose as a parent," said Waverman, who is mother to an eight-year-old daughter and sons aged 11 and 14.
In addition to her fashion line for tween girls, Ester Knight creates custom costumes for clients. She has also designed outfits for her own daughters, now aged 11 and 13, such as Red Riding Hood and bird and bee costumes.
"Personally, my kids have never wanted to do the witches and ghosts and goblins and the kind of darker Halloween stuff. We've always kind of done more fun stuff," said Saskatoon-based Knight of MoonStar Designs, who has designed four tween costumes inspired by the seasons for an upcoming kidney foundation fundraiser.
"When you go to the mass-produced costuming, that's pretty much what it is. It's witches and ghosts and goblins, and then you get the other end where for girls and for women it's like sexy waitress, sexy this, sexy that," she added.
Carolyn Danckaert is co-founder of the website A Mighty Girl which has produced a costume guide showcasing girl-empowering costumes from infants to adults. Last year, Danckaert said they received more than 800 photos of "mighty girls" in costume showcasing a large variety of creativity, including one dressed as Marvel supervillain Loki.
In addition to the critiques about some girls' costumes being excessively sexualized, Danckaert noted that virtually every costume is feminized, pointing to those depicting a particular profession as an example.
"Say you have a firefighter costume. For a boy, it actually looks like a firefighter costume whereas for a girl it evokes elements of a firefighter costume, but then it's a skirt or a tutu with a firefighter hat."
Charles Taylor, online marketing manager of Costume SuperCenter — which launched a Canadian site two years ago — said dress length has been raised as an issue by some customers, where they've recommended adding leggings or stockings so the looks aren't as revealing. He noted there hasn't been much demand for more gender-neutral costumes.
"In fact, demand for us is more in the princess and girly — and the girlier, typically the better. The more girly it is, the more we sell of it," Taylor said.
"I'm sure there's definitely a segment of the population that wants the more neutral (costume) ... but we find the cute, girly costumes are what the girls like to wear."
Trisha Lombardo, marketing co-ordinator at Spirit Halloween, said they try to provide "family-friendly costumes" to girls and tweens and are offering a number of unisex costumes.
"We're not trying to promote anything for young girls that is out of their realm or too adult for them to be able to portray," she said, noting that they do sell tights, leggings and bodysuits for those wanting to feel less exposed in their costumes.
Still, Lombardo acknowledged there are some people who do want to adopt a sexy look for Halloween — but she feels those are adults, not girls or tweens.
"We can't ignore that some adult women want to be sexy, so we do cater to that," she said. "But we also cater to the female that wants to be a little more conservative, that wants to have fun and not show so much skin. ...
"Halloween's the one night of the year where people get to be whatever or whoever they want. So we want to make sure that they're comfortable and able to be that."
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