Blocked tear duct affects 5-20% of newborns. Tear duct (connects inner eye corner to nose) doesn't open fully at birth, causing tears and discharge. Symptoms: watery eyes (tearing without crying), yellow/white discharge in eye corner, crusting on eyelashes (especially after sleep), mildly red or pink eye white. Usually affects one eye but can be both. Most blocked tear ducts open on their own by 12 months. Different from pink eye - discharge is white/yellow (not green), eye white is not very red, and baby seems comfortable.

Babies get 6-10 colds in first year as immune system develops. Symptoms: runny/stuffy nose, sneezing, mild cough, low fever (<102°F), fussiness, trouble sleeping. Colds are viral - antibiotics won't help. Most resolve in 7-10 days. NO cold medications for babies under 2 years (dangerous side effects). Congestion makes feeding difficult since babies can't breathe through mouth while nursing.

Croup is viral infection causing swelling around voice box and windpipe. Symptoms: Distinctive barking cough (sounds like seal), hoarse voice, stridor (high-pitched squeaking when breathing in), trouble breathing (worse at night). Most common in fall/winter. Typically lasts 3-7 days. Starts with cold symptoms, then barking cough develops on day 2-3. Worse at night. Scary but usually mild. Caused by parainfluenza virus. Most common in babies 6 months to 3 years.

Ear infections are very common in babies (peak 6-15 months) because Eustachian tubes are short and horizontal. Often follow colds when fluid builds up behind eardrum and gets infected. Symptoms: pulling/tugging at ears, crying (especially when lying down), fever, trouble sleeping, fluid draining from ear, fussiness, loss of appetite, trouble hearing. Not all ear infections need antibiotics - many resolve on their own.

Fifth disease is viral illness caused by parvovirus B19. Classic symptom: Bright red cheeks that look like they've been slapped, followed by lacy red rash on body/limbs. Mild illness for most children. First symptom may be low fever and cold symptoms, then after a few days the distinctive red cheeks appear. Rash may come and go for weeks, triggered by sun, heat, exercise, or stress. More common in ages 5-15 but can occur in babies. By the time rash appears, child is no longer contagious.

Common viral illness in young children, caused by coxsackievirus. Symptoms: fever, sore throat, painful mouth sores (on tongue, gums, inside cheeks), rash on hands and feet (sometimes buttocks). Highly contagious but usually mild. Most common in summer/fall. Lasts 7-10 days. No treatment - just manage symptoms. Baby is contagious even before rash appears.

Pink eye is inflammation of white part of eye. Types: Viral (most common, accompanies cold), bacterial (thick yellow/green discharge), allergic (itchy, watery). Symptoms: red/pink eye whites, discharge (clear, white, yellow, or green), crusting (especially after sleep), tearing, itching. Viral and bacterial pink eye are highly contagious. Allergic is not contagious.

Roseola is common viral illness in babies 6 months to 2 years. Classic pattern: High fever (103-105°F) for 3-5 days with no other symptoms, then fever breaks and pink/red spotty rash appears. Caused by human herpesvirus 6 (HHV-6). Baby seems otherwise well despite high fever. Once rash appears (on trunk, spreading to arms/neck/face), baby is feeling better and fever is gone. Scares parents because high fever appears with no obvious cause. But once you see the characteristic rash after fever breaks, diagnosis is clear.

RSV is common respiratory virus that infects almost all children by age 2. For most, causes mild cold. For some (especially under 6 months), can cause bronchiolitis - serious lung infection. Symptoms start like cold: runny nose, cough, fever. Then: rapid breathing, wheezing, retractions (skin pulling between ribs), decreased eating, lethargy. RSV season: October-March. Most dangerous for premature babies and those with heart/lung conditions.

Stomach flu is viral infection causing vomiting and diarrhea. Common causes: rotavirus (vaccine helps prevent), norovirus, adenovirus. Symptoms: vomiting, watery diarrhea, fever, stomach cramps, loss of appetite. Usually lasts 1-3 days but diarrhea can persist up to 10 days. Main danger is dehydration, especially in babies under 6 months.

Thrush is yeast infection (Candida) in baby's mouth and sometimes mother's nipples. Very common in newborns and breastfed babies. Symptoms in baby: White patches on tongue, inner cheeks, or gums that don't wipe off easily, fussiness during feeding, white coating on lips, refusing breast/bottle. Symptoms in mom: Pink, shiny, itchy, or painful nipples, shooting pains during/after feeding. Through is not dangerous but can make feeding painful. Spreads between baby's mouth and mom's nipples during breastfeeding.