Gulp.

A Pennsylvania mom is under fire after posting a picture of her breastfeeding not only her own child, but her friend's son, all to raise awareness about "milk sharing."

"So much love between these milk siblings," Jessica Anne Colletti, 27, said in her post for the Mama Bean parenting blog on Saturday. "It's a special bond between us all."

Colletti began sharing her milk with Mateo, the son of friend Charlie Interrante, who was having trouble with formula and experienced constipation. She now refers to Mateo as one of her sons and says she and Interrante, 25, are inseparable. In fact, the single mother moved in with Colletti and her husband, Ben, last month.

As for the backlash Colletti has received, she says it was "totally expected" because she believes critics are misinformed and wrongly sexualize breastfeeding.

According to the FDA, milk sharing is okay as long as milk donors have been screened for infectious diseases.