Senator Tammy Duckworth and her newborn baby just made history.

Duckworth brought her newborn baby, Maile, to the Senate floor to vote Thursday just weeks after giving birth — marking a pivotal moment for lawmakers and their families a day after the Senate passed, without objection, a resolution that allows senators to bring their children under one year onto the floor.

Carrying Maile in her arms, the senator appeared on the floor for the first time since giving birth to vote no on President Donald Trump’s pick to lead NASA, Rep. Jim Bridenstine of Oklahoma. The Senate narrowly confirmed Bridenstine, 50-49.

Duckworth, 50, who became the first sitting U.S. Senator to give birth while in office when she welcomed her baby earlier this month, pushed for the resolution to ensure she would be able to attend Senate votes and introduce legislation while the mother of a newborn.

Earlier Thursday, Duckworth tweeted an image of an ensemble consisting of a duckling onesie and a teal sweater for her newborn daughter’s Senate debut.

“I may have to vote today, so Maile’s outfit is prepped,” the Illinois Democrat tweeted Thursday. “I made sure she has a jacket so she doesn’t violate the Senate floor dress code (which requires blazers).”

“I’m not sure what the policy is on duckling onesies,” she added, “but I think we’re ready.”

Senators are required to take votes in person. As such, without the new rule in place, it would have been more difficult for Duckworth to do her job.

“Parenthood isn’t just a women’s issue, it’s an economic issue and one that affects all parents — men and women alike,” Duckworth said in a statement after the birth of her second child. “As tough as juggling the demands of motherhood and being a Senator can be, I’m hardly alone or unique as a working parent, and my children only make me more committed to doing my job and standing up for hardworking families everywhere.”

On Wednesday, Duckworth applauded her fellow senators, saying they were “leading by example and sending the important message that working parents everywhere deserve family-friendly workplace policies.”

Duckworth is one of 10 women to give birth while in Congress. In fact, she welcomed her first child, Abigail, when she served in the U.S. House of Representatives. The trail-blazing senator is an Iraq War veteran who lost both of her legs and damaged her arm in combat.

Unlike the senators, Maile (and all other future babies to come on the Senate floor) won’t have to worry about a dress code. Sen. Amy Klobuchar told WBUR despite questions from other senators about one, babies will be exempt from the Senate dress code.

Get our Politics Newsletter. The headlines out of Washington never seem to slow. Subscribe to The D.C. Brief to make sense of what matters most. Please enter a valid email address. Sign Up Now Check the box if you do not wish to receive promotional offers via email from TIME. You can unsubscribe at any time. By signing up you are agreeing to our Terms of Use and Privacy Policy . This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply. Thank you! For your security, we've sent a confirmation email to the address you entered. Click the link to confirm your subscription and begin receiving our newsletters. If you don't get the confirmation within 10 minutes, please check your spam folder.

Contact us at letters@time.com.