| Manning declared her new identity the day after sentencing |
US President Barack Obama has commuted Chelsea Manning's sentence for leaking documents to Wikileaks in 2010.
| Chelsea Manning, then Bradley, was convicted in 2013 |
The commutation reduces Manning's sentence but is not a pardon, which some campaigners had called for.
More on Chelsea Manning
Manning's uncle, Kevin Fox, referring to Chelsea as a man, told the BBC the family was "over the moon". "It's sooner than we expected - we didn't expect his case even to be looked at for another three or four years," Mr Fox said.
Manning lived for four years as a teenager in Wales. Her Welsh family said in a statement that they were "overjoyed", adding that there would "always be a welcome for her here in Wales".
Manning twice attempted suicide last year at the male military prison where she is being held at Fort Leavenworth, Kansas. She also went on a hunger strike last year, which she ended after the military agreed to provide her with gender transition treatment.
Mr Obama granted commutation of sentences to 209 individuals and pardons to 64 others, in one of his final acts as president.
Edward Snowden, a former National Security Agency (NSA) contractor who leaked information on mass surveillance programmes before fleeing the US, was not granted a pardon.
Russian authorities said on Wednesday that Mr Snowden had been granted a two-year extension to his temporary asylum in the country.