Grace Gealey and Trai Byers are building their own empire!

The stars of Fox’s hit series Empire are engaged, E! News confirms. Byers, 33, threw a surprise birthday party for Gealey, 31, at Chicago restaurant Kinmont Sunday night. “She thought it would just be the two of them going to dinner, but when they got there, he had arranged a party for about 20 of her friends and family members to surprise her,” a source says. Gealey was seen wearing a diamond ring at dinner.

The beautiful and talented birthday girl was fêted by several of her Empire co-stars, including Kaitlin DoubledayGabourey Sidibe and Jussie Smollett.

“They are definitely going strong,” a source says of the future spouses. “They make a really cute couple.” Romance rumors began swirling in the springtime, but neither Gealey nor Byers have discussed their romance in press interviews.