Sleep like a baby

Hopefully not. From this HHMI virtual museum on biological clocks (of all sorts, and not just the Marisa Tomei variety), comes this figure [1]:



It looks to me like the parents reach exhaustion about 12 weeks in and stop caring if the baby wants to sleep or not.

[1] Adapted from Nathaniel Kleitman and T. Englemann "Sleep Characteristics of Infants," Journal of Applied Physiology, Vol.7, 1953