Anyone who has been a stay-at-home mom knows that it's not easy. But many people who haven't been one assume that it can't be that hard. I mean, what's so hard about taking care of a baby or a toddler or two? Don't babies basically just lie there? Don't you have all kinds of free time while they nap?

It's hard to describe what it's like to those who haven't experienced the near-constant demands of hands-on, full-time mothering. I've had multiple jobs in my life, from flipping fast food burgers to teaching in public schools, and nothing compares to being a mom. Don't get me wrong, it's wonderful in a million ways, but it's friggin' hard. My kids are all in the double digits now, but I remember those early years of staying home with my wee ones and feeling totally and completely spent by the end of the day.

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Many moms I know lament that their husbands don't seem to understand why they are so exhausted when "all they do" is "just stay home" with the kids all day. That's probably why this dad's photo of a steamy shower door has resonated with so many.