Both of our PJs are usually Christmas-themed and color-coded. Jennifer's tend to be blue or purple with some extra lacy, girly touch. An assistant principal at an all-girls' high school, Jennifer is conservative in her fashion choices; she's never met a coordinated set she doesn't like.
I'm much more laissez-faire: I like my sleepwear sans frills and I prefer to mix and match. My Christmas pajamas are always red. Last year, Mom selected a pair of wide-legged pants and matching scoopneck long-sleeved T dotted with wineglasses. Does my mom know me, or what?
Mom says she started the PJ fashion tradition because she didn't want her children opening their presents on Christmas morning in ratty pajamas. That's bad for pictures. "I wanted you all to look pretty," she told me last week.
We weren't just pretty, we were adorable.
My eyes get moist with nostalgia looking back at the succession of Polaroids that show two '80s kids in spiffy pajamas and sponge rollers playing with dolls and tabletop video games and wrestling with velvet dresses.
Over the years, Mom's sleepwear choices for us followed fashion trends. Some years we got leggings with long T-shirts (a la Flashdance). During our teenage years, we got Victoria's Secret tanks with baggy drawstring bottoms. One year, Jennifer asked for big-girl footie pajamas. (She got them, I didn't.)
However, the stylish tradition was way more important than the pajama of the moment. If there is one thing I know for sure, it's that my mom loves us. Whatever she doesn't say with over-the-top emotion, she says with fashion, especially at Christmastime. There weren't just pajamas under our tree, there were velvet dresses - mine were always red, too - with tights, black patent leather shoes, and hat and scarf sets she made herself.
Thinking about pajamas made me wonder about the ties between fashion and holiday traditions. Stylishly speaking, Christmas traditions are much more about comfort than flash, said Clara Henry, director of the fashion design program at Philadelphia University.
Unlike Easter and Mother's Day, when fashion tends toward pastel hues, Christmas is much more playful.
"Fashion choices around the holidays are about cuddling and being together," Henry said. "The season is about whimsy. That's why there are sweaters with sparkling antlers and elf hats."
And then there is the fact that Christmas gifts are traditionally about necessities. That is why, Henry said, families tend to exchange socks, underwear, slippers, sweaters, and, yes, pajamas.
This Christmas, while my sister and I are opening up our pajamas from our mom, my 5-year-old niece will be tearing open a box of PJs of her own. Something tells me that Mrs. Claus will be leaving a pair of the Hello Kitty variety Saturday night.
After Mom hands us our boxes, she'll go back to her rocking chair and Jennifer or I will hand Mom a box filled with affection, tradition, and pajamas of her own to open.
With love from Mrs. Claus, of course.
Contact fashion writer Elizabeth Wellington at 215 854-2704, email@example.com, or @ewellingtonphl on Twitter.