Hi thanks for your question
The recommendations for booster doses of rabies
vary for different persons.
Those working with virus like laboratory men and scientists are tested for immunity every 6 months and if titer is low a booster dose is given every 6 months.
That dealing with dogs, their antibodies
titer is checked every 2 years and if antibodies titer low booster dose is given every 2 years.
For rest, at risk, the immunity is checked every 3 years and not later than 7 years.
If antibodies titer is low booster dose is given.
Since your nephew has received vaccine
one year back, his antibodies titer should be checked (difficult to do) and if anybody’s titer is low booster doses should be given.
Hope I answered your question