I think that means Seize Mother's Day. But maybe not - I am really only fluent in Pig-Latin.
As far as I know, we all have mothers. I don't think Science has done away with that yet. And I'm going to boldly state that the majority of readers of the Is That Funny blog love their mothers. Why? My research shows that people who $*#%-ing love Zeichen Press also $*#%-ing love their mothers. My research involved a picture-day slideshow and ham salad sandwiches. Also, $50 bills stuffed in a piñata. It was unorthodox but revealing.
But, don't let me tell you what to do. I mean, if you don't want to celebrate your mom (OR mother-in-law!) on this one day of the year, that's your decision. I'm sure she won't be hurt at all. It will never be brought up again.