Following her breakup with Magid, Ratajkowski fell for Sebastian Bear-McClard, a movie producer, in February 2018. Just two weeks after they started dating, the couple said "I do" in a New York City courthouse. Ratajkowski revealed the news on her Instagram Story, writing, "Sooo, I have a surprise. I got married today," along with a number of posts from the casual ceremony.
The pair kept their relationship private for the next two years. But in October 2020, Ratajkowski announced they were expecting their first child together in a digital cover story with Vogue. "I'm completely and undeniably helpless when it comes to almost everything surrounding my pregnancy: how my body will change, who my child will be. But I'm surprisingly unbothered. Instead of feeling afraid, I feel a new sense of peace. I'm already learning from this person inside my body. I'm full of wonder," she explained. In March 2021, the "Gone Girl" actor revealed on Instagram that her baby, Sylvester Apollo Bear, was born.
Just a little over a year after the birth of their first child, Ratajkowski and Bear-McClard hit a rough patch and went their separate ways in July 2022. According to a source with Page Six, Bear-McClard allegedly cheated on Ratajkowski, which led the "Entourage" actor to file for divorce. In a November 2022 interview with Harper's Bazaar, Ratajkowski touched on her divorce, saying, "I feel anger, sadness. I feel excitement. I feel joy. I feel levity. Every day is different. The only good thing I know is that I'm feeling all those things, which is nice because it makes me believe that I'll be okay."