As the baby formula shortage continues, moms are doing what we do best — having each other’s backs. From Nextdoor and group chats to FB and Twitter, there are threads with moms offering up extra formula stock and even unused breast milk. While there is nothing better than a fierce community of moms, we asked experts about the safety of not knowing the backstory of your formula supply. In the first-ever parent briefing at the White House (yes, things are so bad for moms right now, they invited us in for an official update), Admiral Dr. Rachel L. Levine, M.D., explained how to navigate getting formula from someone you don’t know.