The Brady Bunch had six kids. So what? Cheaper by the Dozen had 12. Better but not good enough. This movie has 18! That's, like, Cheaper by the Dozen and a Half because we all know the more kids, the funnier the movie, right?
In the 1968 original with Lucille Ball and Henry Fonda, they each had young children despite the fact that Lucy was 56 and Fonda was 61. And this was nearly 30 years before Viagra. But this remake is as formulaic as they come.
Eighteen children simply means that every 15 minutes, you'll see a kid you never noticed before. Essentially, this is just a romantic comedy about two widowed people (because decent folks can only find themselves alone if their spouses die) who have little in common aside from an apparent tendency to forgo birth control. When they marry on a whim and bring their excessive broods together, none of the kids get along. Thus begins an elaborate plot to break them up—a sort of Parent Trap in reverse. What follows are a series of schemes involving a lot of repetitive slapstick that always ends with several people covered in bright-colored goo.