Between weeks six and eight the social smile arrives, the first smile that answers your face rather than gas or sleep. The AAP lists this as a key early milestone. Alongside it comes cooing, soft vowel sounds he makes when you talk back, and smoother visual tracking as his eyes follow a slow-moving toy across the midline. He also starts to hold eye contact for several seconds. These are the first real conversations, and they are built from your responses, not from toys.

Around week eight most babies begin the second leap on the Wonder Weeks calendar, the world of patterns. After a fussy window, he starts to notice that things repeat: the same face, the same rattle sound, the same shape on the mobile. He may suddenly cry in the bath or stare hard at a pattern for minutes. The leap calendar calls this the shift from raw sensations to simple patterns. It is temporary, and the skills it leaves behind, noticing and predicting, stay.

By weeks five to eight feeding stretches out a little. Instead of ten to twelve feeds a day, many babies settle into seven to nine, with a longer gap at night. The AAP still advises on-demand feeding, so watch the baby and not a strict clock. The number of wet nappies stays the key check, six or more a day. A sudden refusal to feed or a big drop in nappies is a reason to call the doctor, not to push harder.

Between six and ten weeks some babies begin sleeping a stretch of four to six hours at night, though the AAP is clear that waking for feeds is normal and healthy in this age range. Full night sleep is not a milestone to chase. A baby who sleeps longer at night usually does so because daytime feeds were full, the room was dark and cool, and the last wake window was not too long. Cluster feeding in the evening often comes just before a longer stretch; it is a feature, not a failure.

From about week six to week ten, many babies have a fussy period in the late afternoon and early evening, often called the witching hour. It is not caused by bad parenting. The AAP notes that crying typically peaks around six to eight weeks and then declines. Some evening crying is the normal discharge of a long day of new stimulation. Colic, a separate pattern, is defined as crying for more than three hours a day, more than three days a week, for more than three weeks, in an otherwise well-fed, healthy baby.

Normal fussiness comes and goes and a baby can still be comforted. Colic is the rule of threes: over three hours of crying a day, more than three days a week, for more than three weeks, in a healthy, growing baby, and it settles by four months. Reflux is spitting up that is effortless and painless; call the doctor if it becomes forceful, projectile, green or bloody, if he arches in pain with feeds, refuses to feed, or is not gaining weight. The AAP says these are clinical calls a pediatrician makes, not ones to self-diagnose.

Weeks five to eight hold the two-month well visit, which comes with the first round of vaccines. The AAP schedule gives several shots at two months. Expect a fussy, low-grade-fever day afterward, and plan a quiet day, not a family outing. By now the birth weight is well behind you and the growth chart matters more than any single number. This is also the window when the social smile shows up, so keep two or three photos for the record.