Heather Tomoyasu, from Brooklyn, America, took photos with her husband and their two-year-old son to share their pregnancy announcement.
Tomoyasu and her son then posed for photos wearing the same clothes a few times every week and edited the snaps into a stop motion video.
The pictures capture their growing excitement as they discover the sex of the babies.
And document Tomoyasu's growing baby bump.
Right up until Tomoyasu gave birth on 6 October 2015.
One day Tomoyasu says she'll show her twins this video as proof of their prenatal fame.