(By the way, one day I sent a picture of a dress to my sister-in-law on WhatsApp. She told me that Instagram sent her an ad 5 minutes later, with the exact same

(By the way, one day I sent a picture of a dress to my sister-in-law on WhatsApp. She told me that Instagram sent her an ad 5 minutes later, with the exact same dress. It was so unlikely to be random that I checked right away to see if pictures were safe. It turns out that pictures received and sent are shared within all Facebook apps - Facebook, Messenger, Instagram -, at least on iOS)