Who is Ms. Rachel and why are your kids obsessed with her?

Who is Ms. Rachel and why are your children all of a sudden begging to watch educational videos from “Songs For Littles"?

If your child has become a fan of Ms. Rachel, they are not alone. If you find yourself humming along to songs about opposites or how to learn colors, you are also not alone.

Heralded a hero by parents, Ms. Rachel is a celebrity to the 4-and-under crowd and best known for her educational videos entitled "Songs For Littles."

The educator and songwriter has become an internet sensation and there's no slowing down this musically inclined preschool teacher turned social media star.

But who is Ms. Rachel? And why is she so popular?

Who is Ms. Rachel?

Rachel Griffin Accurso, known online as Ms. Rachel, is a New York City preschool teacher turned YouTube and TikTok star who is making a big impact on children around the world.

Alongside her band, which includes her husband, Broadway composer Aron, Accurso produces a popular YouTube channel for toddlers and preschoolers with educational videos and music classes called "Songs For Littles."

Accurso began the channel after her son, Thomas, was diagnosed with a speech delay.

"His first word was at 2 years and 8 months and it was 'mama' and I had waited for that for so long," Accurso tells NBC News' Gadi Schwartz. "As a parent you want to do anything you can to help them and it's not our fault when our child has a speech delay. A lot of things I teach are things I wish I had known for my son."

Ms. Rachel YouTube

Accurso, who has a master's degree in music education from New York University, brings her viral videos to life in her one-bedroom apartment’s recording studio.

"I needed experts to help me," she says. "I thought, 'Wouldn't it be great if there was a show that really encouraged language development and worked on these important milestones and was slow-paced and a real person and very interactive?'"

She says she could not find a show that met her son's needs, so she decided to make one.

"I kept searching for this show for him and we couldn't find it, so I was like, maybe we can try to create it and maybe it would help more kids," Accurso says.

Ms. Rachel Songs For Littles

Ms. Rachel's "Songs for Littles" YouTube channel has more than 2 million subscribers and over 1 billion views.

The channel's description explains that parents can expect "toddler learning videos and baby learning videos that help children learn to talk, learn letters, numbers, colors, animal sounds and more."

Ms. Rachel's success can be credited to the simplicity of each video.

She employs close-ups of her mouth, building in pauses for responses and using sign and body language to encourage speech and language.

Accurso's mission is simple.

“It always comes back to — am I helping?” she says.

Ms. Rachel Cast

While Ms. Rachel is the star of the show — with help from puppets Georgie and Herbie operated by Aron — there is a cast of musical and technical professionals who help “Songs for Littles” come to life.

Notable Ms. Rachel cast and crew include Beth Jean, Jules, Natalie Kaye Clater, Frida Matute, Alexa Smith, Keisha Gilles, Angelo Soriano, Simon Kafka and Dennis Stowe.

This article was originally published on TODAY.com