There are 66 sleeps (66 days) until December 28 (Monday, December 28, 2026).
There are 66 days until December 28 (Monday, December 28, 2026) — one sleep per night.
One sleep per night between now and the big day — tonight is the first sleep, and the morning after the last sleep is December 28. Sleeps are the same as days.
66 sleeps is 9 weeks and 3 sleeps.