How long does it take for an average brown thrasher to grow up?

Brown thrashers typically fledge, or leave the nest, about 12 to 13 days after hatching. After fledging, they continue to be dependent on their parents for food and care for several weeks. By around 4 to 5 weeks post-fledging, they generally become more independent and start foraging on their own. However, full maturity takes longer, as they usually reach sexual maturity in about one year.