The prospect of boarding a plane with a small child is scary for most parents. Chelsea Williams and her husband were flying with two — their 5-week-old baby, as well as their 2-year-old daughter.

But Williams and her husband had done their best to prepare, picking a shorter flight, boarding last to stop their baby from growing restless on the plane, and choosing seats at the back so they had more room to soothe the baby.

Williams, 28, also researched the best ways to pacify babies in the air, and learned that breastfeeding during takeoff and landing is an effective way of soothing babies and protecting their ears from hurting due to the cabin pressure.

Instead, during her TUI flight from Manchester in the United Kingdom to Almería, Spain, on July 30, Williams says cabin crew asked her to stop breastfeeding her baby, who was wearing a loop seat belt on her lap, during takeoff — in an incident that left her “on the verge of tears” and dealing with a crying baby and toddler.

When Williams’s husband messaged TUI’s customer service later, to ask if she could breastfeed during takeoff and landing on their return flight on Sunday, the airline responded that while “there are no official restrictions however we would not recommend it because it could make other people uncomfortable,” she added.

The response was “absolutely shocking” and felt like “discrimination against breastfeeding babies and mums,” Williams, a software engineer from North Wales, said in an interview Tuesday.

The trouble began when a member of the cabin crew who was performing preflight safety checks informed Williams that she “couldn’t feed for takeoff and landing; it wasn’t permitted,” Williams said.

Williams was shocked but, believing she may have overlooked in her research some valid safety reason for why she couldn’t breastfeed during takeoff, she complied.

As soon as she stopped nursing, her baby began “crying quite drastically.” Then things got worse: “The toddler was crying. I was sweating. I was on the verge of tears. I felt like everyone’s eyes were on us,” she recounted. She said her baby was “obviously in pain,” hungry and sleepy. Williams “wasn’t really sure what to do” and “didn’t want to cause a scene,” she said.

Eventually, when the fastened seat belt lights turned off, Williams nursed her daughter. Altogether, it took her about an hour to settle her baby and help her fall asleep, she said.

Williams’s story has sparked outrage on social media, with other mothers sharing their experiences of breastfeeding on planes.

Some called the timing of the incident ironic, given it happened just before World Breastfeeding Week, a global event designed to promote breastfeeding and raise awareness about the barriers breastfeeding women face.

The right to breastfeed in public is protected by law in many countries, including the United Kingdom under the Equality Act of 2010, which prohibits anyone from treating a woman unfavourably because she is breastfeeding.

In the United States, there are laws protecting breastfeeding in any public or private place in all 50 states, the District of Columbia, Puerto Rico and the Virgin Islands, according to the U.S. Centers for Disease Control and Prevention.

The U.K. Civil Aviation Authority, which is responsible for regulating air safety, states that infants younger than 2 must be secured by a seat belt loop, or a child restraint device when the seat belt sign is on.

Henry Heming, a spokesperson for the regulator, told The Washington Post via email that “there are no regulatory restrictions on breastfeeding during takeoff and landings, and this is not considered to be a safety matter.”

Many major airlines state that breastfeeding is allowed at any time during a flight, and the CDC is among those that recommend breastfeeding during takeoff and landing to protect babies “from ear pain due to cabin pressure changes.”

Newborn babies have tiny stomachs and may need to breastfeed every two hours or as often as every hour, the CDC adds.

“It is unethical and immoral to deny a breastfed baby access to food, fluid and comfort by discouraging responsive breastfeeding,” Lyndsey Hookway, a lactation consultant based in the United Kingdom, said via email when asked about the incident.

She said there are double standards when it comes to breastfeeding: “We wouldn’t discourage bottle feeding on the flight, or refuse to allow people to suck boiled sweets during take-off and landing.”

A spokesperson said in an email Tuesday that TUI is “really sorry for the distress caused to Ms Williams and her infant.”

“As a family-friendly travel company we support breastfeeding on our flights at any time,” the airline said. “We are currently conducting an urgent internal investigation and will be making sure that all colleagues are retrained on our breastfeeding-friendly policy.”

On the return TUI flight, Williams breastfed her baby, and no one tried to stop her, she said. Nonetheless, she hopes her story will push the airline to better train its employees to handle situations like hers and “include a statement that breastfeeding is encouraged on board in their safety/welcome briefing on board all flights.”

She added that she hoped TUI would apologize, explain why its employee said that breastfeeding during takeoff and landing was unsafe, and clarify whether that rule “also applies to bottle-fed babies, adults eating or drinking during takeoff, too.”

Hookway argues it is “unnecessary” to ask for “permission in advance to breastfeed on a flight.”

“Asking the question provides an opportunity for ill-informed staff to refuse,” she said, adding that there is a need for “awareness training” of personnel who interact with mothers and babies.

“The assumption that a baby may feed wherever and whenever they want/need to should be the standard,” she said.