During the first three months of life, babies tend to cry the most.
According to available information, newborns cry and get fussy sometimes. It's normal for a baby to cry for 2–3 hours a day for the first 6 weeks. However, the period when babies cry the most is during the first 3 months of their lives. New parents often experience sleep deprivation and adapt to life with their little one.
Therefore, instead of pointing to a specific month, it is more accurate to state that babies cry the most during the first three months after birth.