(CNN) In a rare move, the Senate on Wednesday night voted to change longstanding rules to allow newborns -- for the first time -- onto the Senate floor during votes.

The rule change, voted through by unanimous consent, was done to accommodate senators with newborn babies, allowing them now to be able to bring a child under 1 year old onto the Senate floor and breastfeed them during votes.

Illinois Sen. Tammy Duckworth, who gave birth this month to her second child, becoming the first US Senator to do so while in office , spearheaded the push for the rule change and applauded her fellow lawmakers who she says helped to "bring the Senate into the 21st Century by recognizing that sometimes new parents also have responsibilities at work."

"By ensuring that no Senator will be prevented from performing their constitutional responsibilities simply because they have a young child, the Senate is leading by example and sending the important message that working parents everywhere deserve family-friendly workplace policies," Duckworth said in a statement after the vote.

Duckworth decided to take her maternity leave in Washington, DC, rather than in Illinois, to be able to be on hand and available to cast her vote in the Senate if needed. But she expressed concern about the complex and strict Senate rules, which might impact her ability to do so while caring for -- and breastfeeding -- her newborn.

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