We're used to mother-in-laws overstepping the mark when it comes to their grandkids. It's practically a given that MILs will at some point—and with the best of intentions—tell you how you should and shouldn't do everything baby-related based on their own outdated mothering experiences.

But when it comes to mother-in-law interference, this story is the ultimate. Imagine for a moment that granny is staying over while your husband is away, to help you care for your baby. In the middle of the night, you hear your child fussing. You wait a little bit, and when all goes quiet you enter his room only to find your MIL with her nipple in your baby's mouth!

Unbelievably, that's what happened to a reader who wrote in to Emily Yoffe (aka Dear Prudence) at Slate. The mother-in-law in question claimed to be trying to calm the baby by letting him suckle her (and presumably didn't want to disturb the mother). 

The woman was outraged, ordered her MIL to leave the house first thing in the morning, and even contemplated involving the police. 

Shocking and inappropriate though granny's actions clearly were, was she actually breaking the law? Prudence didn't think so.

"Your husband needs to have a very serious talk with his mother about boundaries—emotional and physical," she responded. "He needs to explain that if she can’t respect and understand them, she will not have access to her grandchild. I’m also wondering if she might possibly need a mental health work-up because her behaviour was just bizarre." 

How would you have handled the awkward situation, especially given your husband was out of town at the time? Is the breast basically just a comfort piece, or a sacrosanct gift for mom—and mom alone—to bestow onto her babe?