A 2018 Pediatrics study found sleeping through the night overrated. Though, to be honest, I have skepticism about the potential for its validity due to:
- it was based on self-reporting by the mothers
- it only measured development through age 3.
RESULTS: Using a definition of either 6 or 8 hours of uninterrupted sleep, we found that 27.9% to 57.0% of 6- and 12-month-old infants did not sleep through the night. Linear regressions revealed no significant associations between sleeping through the night and concurrent or later mental development, psychomotor development, or maternal mood (P > .05). However, sleeping through the night was associated with a much lower rate of breastfeeding (P < .0001).
— Pediatrics. 2018 Dec;142(6). pii: e20174330. doi: 10.1542/peds.2017-4330. Epub 2018 Nov 12.