Mark and Anna Sansone, from Japan, put together the moving Welcoming Mila video using photos and short film clips to create a stop-motion effect.
The footage starts with Anna standing in the family's living room with a flat tum. As her stomach starts to grow, the couple's two-year-old daughter, Amelie, toddles in and out of shot, adding an extra element of cuteness to this already adorable film.
Around Anna's feet various toys and baskets of washing appear and disappear, as family life continues as normal while her pregnancy progresses.
The video ends when Amelie kisses her mum's stomach and - as if by magic - her baby sister appears.
If only giving birth was so easy!
Story continues after the video
Mark and Anna are well practiced in the art of the pregnancy time-lapse video, as in 2012 they uploaded a similar video showing Anna's pregnancy with Amelie condensed into 90 seconds.
Since being uploaded onto YouTube their Introducing... video has been viewed more than 11 million times, and now they're set to take the internet by storm once more.
Mark said Amelie isn't yet aware that she's a viral star, but watching the first video and filming the second has helped her to understand that she was about to become a big sister.
"She certainly doesn't know her video became popular," Mark told ABC 30. "Amelie is just starting to understand that people grow up and this video was a great device to use to help her understand that she was going to have a baby sister soon."
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