Recent, tender, youthful, inexperienced, green, fresh, brood, infants, offspring, progeny...
Another word for not old is young.
infatuation
young man
Infant, toddler
young teen means young teens another word tween
Baby, child, toddler or young
kid: youth: todler
observant
A sapling, shrub, bush.
zatanous
Another word for a young bird is "nestling." This term typically refers to a bird that is still in the nest and dependent on its parents for food and care. Another related term is "fledgling," which describes a young bird that has just acquired its feathers and is learning to fly.
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