Few thoughts strike fear and dread into parents like the prospect of having to make a plane trip with a baby, toddler or young child. If the stress of shepherding sippy cups and electronic toys through the security checkpoint doesn’t leave the grown-ups on edge, it’s the possibility of having to beg a stranger to switch plane seats so they can sit next to their children.

Now, Congress may be stepping in to try to ease some stress.

The Senate added an amendment Monday night to the Federal Aviation Administration reauthorization bill that would allow parents to accompany their children at all times through security checkpoints and would require airlines to allow parents to sit with their children on flights, at no additional cost. The amendment, proposed by Sen. Michael Bennet (D-Colo.), also would require airlines to accommodate pregnant women, such as by allowing them to pre-board.

As more airlines have begun charging additional fees for “premium” or “preferred” coach seats, fewer seats remain for passengers who want to reserve seats next to each other without paying extra. Many of the remaining options are middle seats, rows apart. Some families with multiple children say the additional cost of reserving premium seats together, on top of ticket fares, can be unaffordable.

That can leave parents scrambling for seats adjacent to their toddlers or young children — babies often sit on adults’ laps, but some parents buy a seat for their infant carriers — once they get to the airport. There they’re at the mercy of fellow passengers, who voluntarily switch seats with them or are persuaded to do so by gate agents or flight attendants.

While most passengers eventually switch to accommodate parents — who wants to get stuck babysitting someone else’s sticky, seat-kicking toddler for hours on end? — parents say the seat scramble adds to the stress of flying. Meanwhile, the passengers who agree to switch don’t get the seat that they might have paid extra for or reserved months in advance. Some parents say they pay extra for premium seating with their children just to avoid the uncertainty.

Airlines for America, a trade group for some U.S. airlines, including United and American, says no law is needed because passengers already can sit together without paying additional charges.

“Airlines have always worked to accommodate customers who are traveling together, including those traveling with children, and will continue to do so — without unnecessary federal mandates,” said spokesman Vaughn Jennings. “We believe that customer service decisions are best left to the dedicated and experienced airline employees who interact with and receive feedback from their customers every day — not the government.”

The Senate is debating the full bill but added the amendment by unanimous consent, a Bennet spokesman said. He said the challenge will be keeping it in the bill through the conference negotiations.