But it wasn't just their outfits making headlines. After the musician and model rocked up to the gala and posed for customary photos, fans noticed a slightly awkward interaction between the married couple.
In the footage, Justin places his hand on his wife's belly before she promptly removes it and he puts it swiftly in his pocket (smooth JB, no one noticed a thing). Take a look for yourself.
While Hailey simply could have wanted the photographers to get a full glimpse of her outfit, the small gesture, as well as her outfit in general, sparked a lot of commentary on Twitter.
Take a look.
Could Justin and Hailey be getting a baby, baby, baby? 👀Well, neither of the celebs have confirmed it - so we'll just have to wait and see.
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