The daughter isotope of carbon-14 decay is nitrogen-14.
Carbon-14 decay is most famously known for its application in carbon dating of fossils. It is generated in the upper atmosphere, when cosmic rays cause production of neutrons, which interact with nitrogen. All the living organisms contain a fixed ratio of two isotopes of carbon: carbon-12 and carbon-14. Till the organism (both plants and animals) is alive, it maintains this ratio. However, once the organism is dead, it is unable to replenish carbon-14 and this ratio changes. Carbon-14 undergoes beta-decay, as per the following chemical reaction:
C-14 -> N-14 + `e^-`
In the decay process, nitrogen is generated, thus completing the cycle. Carbon-14 decay process has a half life of about 5730 years and can be used to determine the age of fossils.
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