The singer and her husband Evan Ross welcomed their son Ziggy Blu into the world last month

Ashlee Simpson Ross is showing off her adorable family.

In a post on Instagram Tuesday, the 36-year-old singer shared a loving shot of her three children posing together in honor of Election Day.

In the photo, Simpson Ross' son Bronx Mowgli, 12 this month, with ex-husband Pete Wentz cradles his newborn brother Ziggy Blu in his arms as his younger sister, 5-year-old Jagger Snow, stands below him.

Alongside the photo, Simpson Ross captioned the post, "Future Voters," as her husband Evan Ross did the same with an identical photo on his respective Instagram account.

Fans of the couple sent their love and congratulations to the pair in the comment section of Simpson Ross' post, where one user wrote, "Love the happy faces. Good job mom and dad," as another added, "OH MY GOD! All of them are so cute!"

Last month, Simpson Ross and her actor husband welcomed Ziggy. The couple announced the happy news on Instagram over the weekend, where Simpson Ross wrote "10-29-2020 Ziggy Blu Ross. Our sweet boy has arrived! I'm over the MOON we are so Blessed" alongside a photo of her son wrapped up tightly with the duo's hands resting gently on top of him.

"I'm in heaven," Ross wrote along with the same photo of their baby.

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Simpson Ross announced her pregnancy in late April, sharing photos of herself and her husband, who is the son of Diana Ross, holding up a positive pregnancy test on Instagram.

"We are pregnant and we are so excited to share it with everyone. Baby #3," Simpson Ross captioned her post, while her husband wrote alongside his, "The fam is growing. ♥️ Ash and I can't wait to welcome the newest addition."

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

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The couple previously opened up to PEOPLE in August about their family, with Ross saying that he was "so excited for this little one on the way."

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!"

Still, when it came time to telling big sister Jagger about her younger brother, there was a bit of an adjustment. "She was so upset because she really wanted a sister," said Ross.

But "she's come around to it now," added Simpson Ross of her daughter. "Now she's going to be the queen forever!"