Seung Lee has created a tangible, very soft representation of his baby’s first year of sleep patterns in the form of a knitted blanket. Lee collected the sleep data by manually logging it with the Baby Connect app, and used JavaScript and Python to convert the data to visualize the knitting pattern. He then built a browser-based HTML/Javascript tool that kept track of the stitch colors and allowed him to reference it wherever he was knitting from. The result is The Sleep Blanket, a beautiful keepsake that tells the story of the baby and parents’ first year together.

The 42 x 45-inch blanket is comprised of 185,000 stitches and took Lee more than three months to complete. With each row representing a single day, the top row marks the day the baby was born, and the bottom row is the baby’s first birthday. Each stitch represents six minutes of time spent awake (gray) or asleep (blue), so the blanket is ‘read’ left to right, with the leftmost stitch marking 12:00AM and rightmost stitch ending at 11:54PM.

There's nothing quite like the feeling of someone loving the thing you made for them pic.twitter.com/4U1VBCcKNm — Seung Lee (@Lagomorpho) July 15, 2019

The shift in sleep pattern towards the end of the blanket can be attributed to a cross-country trip the family took to celebrate the baby’s birthday. Lee says he considered adjusting the timestamps, but kept them in as it’s part of the story.

The precision of knitting makes it a great medium for data visualization, such as the time when a German commuter marked all the times her train was delayed in a rail delay scarf. The scarf was auctioned off on eBay for charity at $8,650, but the Sleep Blanket, which captures the chaos of a baby’s first year settling into a steady rhythm, is priceless.