Leah is sitting in her apartment, surrounded by her friends and family who are there to celebrate her 42nd birthday. It looks like a fun party, with everyone sharing dinner and drinks with the birthday girl. But then Leah’s sister Hope walks into the room, filming on her phone while she tells her that she found some people outside.

What happens next is an instantaneous reaction, one that happens so quickly we barely have time to process what’s going on ourselves.

Leah’s face changes immediately upon seeing the “people” Hope has led into the room, morphing into an expression words can barely describe. She looks surprised, yes, but mostly she looks completely overcome with emotion. She quickly jumps to her feet and embraces someone who is outside the camera frame, someone who we can barely see, at this point.

What’s more, Leah is sobbing uncontrollably as she hugs this woman. Her face buried in the strangers’ arms as she tries to calm her down.

If you’re confused, we’re with you. Seeing this video for the first time is touching…but also a bit confounding. Who is this woman that crashed Leah’s birthday party? And why is she having such an intense, emotional reaction to seeing her?

Well, the answer to that question starts 20 years previously, when Leah gave up her newborn daughter for adoption. The baby was adopted by a woman named Anita and named Natalie Rodgers. Leah would never seen her daughter after that point, as a child or as an adult.

Until this moment.

Hope tracked down her biological niece and asked her to attend her birth mother’s 42nd birthday party. It’s her and her adopted mother that she leads through the door to shock the birthday girl.

What we’re not exactly sure about is this: how, after 20 years of not seeing one another, could Leah so immediately know who this young woman is? We can’t know if she’s been keeping up with Natalie online or through pictures somehow. Even if she’s not, however, we can only imagine there must have been some instinctive feeling that a mother gets when she sees her child.

It sounds a little impossible, but maybe she just KNEW that this was her baby, all grown up.

The mother and daughter proceed to have an extremely emotional moment, bringing them both to tears. Leah cannot stop exclaiming “Oh my God” as she kisses her daughter’s hands and holds her face. It’s as if she can hardly believe this is happening, that her birth daughter is safe and really here in front of her!

This has to be one of the best, biggest, and most tearful birthday surprises of all time.

What did you think of this surprise? Did it move you to tears? Share your thoughts on this mother-daughter reunion in the comments section below.