The U.S. Transportation Security Administration has apologized to a Missouri couple after its agents traumatized the family's 3-year-old, wheelchair-bound daughter during a screening and told the mother she could not film the process.

The Feb. 8 run-in Annie Schulte and her disabled daughter had with TSA screeners at Missouri's Lambert-St. Louis International Airport as they were heading to Orlando was caught on tape and posted to YouTube. In the video, 3-year-old Lucy can be seen crying as TSA agents tell Schulte she cannot film the screening.

"To me it was pretty offensive because I was really tuned in when she said that, immediately I'm like, 'OK, hold on, something doesn't seem right.' So I did tell her I was going to wait because I was going to grab my phone," Schulte told ABC News.

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Schulte says it all started when TSA agents asked to pat down Lucy and screen her wheelchair. Schulte asked to tape it, she said, but an agent didn't like that.

In the clip, an agent tells Schulte, "it's illegal to do that." She then tells the agent that they cannot touch her daughter unless she can record it.

"The problem is I don't allow anyone to touch my little daughter without being able to record it," she said.

Her husband, Nathan Forck, said Lucy was treated unfairly.

"It bothers me that my daughter was singled out, specifically because she is in a wheelchair," Forck said.

The family says the final straw came when agents refused to return Lucy's stuffed animal Lamby, even though it had already been scanned.

The TSA issued the apology overnight.

"TSA regrets inaccurate guidance was provided to this family during screening and offers its apology," the agency said. "We are committed to maintaining the security of the traveling public and strive to treat all passengers with dignity and respect. While no pat-down was performed, we will address specific concerns with our workforce."

The family says it accepts the TSA's apology, but wants screeners to receive more training to prevent such an incident from reoccurring.

They eventually made it to their final destination, Disney World, where Lucy got to meet Mickey Mouse.