Daughter surprises mom with pregnancy announcement disguised as birthday cake

Finding out she was going to be grandma was literally the icing on the cake.

— -- This unsuspecting mom was surprised with the best birthday present ever: a delicious cake, and the news she was going to be a grandma all at once.

It took Overfelt a few seconds to process what the cake said while her entire family continued to sing “Happy Birthday,” but once she read the word “grandma,” she lost it.

“It was a gush of warmth and love and happiness,” Overfelt, 58, told ABC News of the touching moment caught on camera. “The next generation is moving in.”

Hinrichs was 10-weeks pregnant when she told her family the good news but said it was a “really hard secret to keep” because they’re all so close-knit.

“If I have the hiccups I tell my family,” the excited mom-to-be from St. Louis said. “But we knew it would be more special with my grandma and aunts and mother-in-law and grandma-in-law all there. We knew it would be more special if everyone was there.”

The family was gathered in April to celebrate multiple people’s birthdays all within one week, so she knew it was the perfect opportunity to collectively catch people off guard for the celebration.

“We’re just so excited and I’m so tickled to death at everyone’s facial expressions with the ugly cry and everything,” Hinrichs, 30, said.

She knew her relatives would be paying close attention to the inscription on the cake because she had done a similarly quirky message on her brother’s fiancee’s birthday cake in January.

"I was reading the cake to see if everybody’s names made it and when it said 'grandma' at the bottom I was just undone," Overfelt said. "The message looks kind of crass but because we are so close, it’s a term of endearment. When it ended in ‘grandma,’ that processing moment was hilarity and awe.”

Hinrichs’ sister was equally surprised at the announcement because she thought Hinrichs had been drinking beer the day before.

“My sister is super-shocked because she thought I’d been drinking that whole Friday and weekend,” she explained. “Derek [her husband] didn’t want anyone to know until everyone was in town on Saturday, so he filled up empty Coors Light bottles with Fresca. It was his idea. I knew if anyone asked I wouldn’t be able to lie. We were just too excited. But I knew if I looked like I was drinking, that no one would ask.”

It’s safe to say the entire family was completely in shock but for Overfelt, finding out she’s going to be a first-time grandmother on her birthday was, quite literally, the icing on the cake.

“I am so happy for her and for Derek,” Overfelt said of her daughter. “That this is going to break their hearts open in such new love. It’s great to think about this little person, this little girl coming our way. So now everything in the world that speaks of girls speaks of this new child coming. It’s really neat.”

The Hinrichs are expecting their baby girl to arrive Nov. 1, their third anniversary. They posted the heartwarming video to Facebook on Father’s Day, right after they found out they were having a girl.