met zijn gat in de boter vallen

Etymology
Derived from the earlier expression.

Literally means "To fall with one's asshole into the butter".

The idiom met zijn gat in de boter vallen as well as its Frisian cognate (mei 't gat yn 'e bûter (or bûterfet) falle) are both typically used to denote someone who was born into comfort, or in Friesland also a woman who married her way into a rich family.

Verb

 * 1)  to be in a comfortable situation through sheer luck; typically used to denote someone born into comfort.