Jessica Colletti has come under fire after posting a photograph of herself breastfeeding her friend’s 18-month old son as well as her own little boy. In the post she describes the children as ‘milk siblings’ and reveals she has been feeding them both for the last year.

“They’re milk brothers … they will always have that bond,” said Colletti, who sparked internet controversy when she posted a photo of herself feeding the boys on the blog Mama Bean.

The arrangement started last year after Colletti met Charlie Interrante, 25, at a magazine photo shoot for new mothers. Interrante mentioned her trouble nursing her son, Mateo, now 18 months old. She wasn’t able to pump her own milk for Mateo at her job as a barber, and Mateo had trouble digesting formula, Colletti said. Colletti offered to feed him along with her own son Lucian, now 16 months — and the women became “inseparable,” Colletti said. The babies, too.