Pregnant Ashlee Simpson and Evan Ross Share Stunning Maternity Photo as They Await Son's Arrival

Evan and Ashlee Simpson Ross are model parents — literally!

The spouses of six years recently posed for a maternity photo shoot ahead of the birth of their second child and first son together, sharing one of the black-and-white images exclusively with PEOPLE.

In the stunning shot, Simpson Ross, 36, bares her baby bump through a black robe, which is open at the front, while looking at the camera.

As she rests one hand on top of her belly, Ross, 32, leans in from behind. Gazing down lovingly at his wife's bump, the second-time father-to-be cradles the bottom of Simpson Ross' belly with one hand.

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Simpson Ross announced that she and Ross are expecting their second child together in April. The couple is already parents to 5-year-old daughter Jagger Snow while the "Pieces of Me" singer shares son Bronx Mowgli, who turns 12 next month, with ex-husband Pete Wentz.

"We are pregnant and we are so excited to share it with everyone. Baby #3," Simpson Ross wrote on Instagram at the time alongside a photo of the couple holding up a positive pregnancy test.

The following month, Jagger and Bronx helped the expecting parents reveal the baby's sex, cutting into a cake filled with blue sprinkles to spill the exciting news to the mom-to-be's Instagram followers.

Simpson Ross and her actor husband previously opened up to PEOPLE in August about their growing family, with Ross (who is the son of Diana Ross) saying he's "so excited for this little one on the way."

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Added Simpson Ross, "It'll be really nice to go back to the newborn phase. Newborn babies smell so good. There's nothing like it. And we can't wait for the snuggles!"

Last month, she celebrated her baby shower with her family, including mom Tina Simpson, sister Jessica Simpson and Jessica's daughters Birdie Mae, 19 months, and Maxwell Drew, 8.

"I'm so grateful to be with my family as we get ready for my baby boy! Not long now!" Simpson Ross captioned a sweet family photo on Instagram. "Thank you @tinasimpsonofficial @whambamevents for making my baby shower so special! ❤️ 📷: @kristingram."

Wrote Ross alongside a picture with his wife from the bash, "Thank you Family for an amazing Baby shower!! Ready for this baby boy!!"