The six-year-old – son of Wakefield Wildcats and former Featherstone Rovers' star Jamie Rooney – can now sit up and walk with a frame following three intense courses of treatment at a world-renowned German clinic.
Generous residents in Brennan's home town of Featherstone and across the district collected £106,000 in just a year to pay for the life-changing therapy.


His proud mum Erika Lund, 27, said: "To see Brennan sitting up for the first time was an unbelievable moment. He has also walked with a lot of help – it's something we've hoped to see for years.
"There are children at the centre who walk unaided, it is our dream to see him do that eventually but we are happy with his progress."
Brave Brennan, a pupil at Streethouse Junior and Infant School, was diagnosed with cerebral palsy when he was one and could not walk, talk or sit up before his treatment began in January.


Erika added: "It's nice for other people to know there is treatment that works and there is hope.
"Brennan can now feed himself better and is more comfortable, any spasms he has are less severe. He also strings words together, is a lot more aware and can express his needs easily rather than getting frustrated.
"He will always have treatment but it might be for two weeks a year rather than months."


Brennan will jet back to the Euromed Rehabilitation Centre – where treatment includes a unique muscle rebuilding programme using specially adapted cosmonaut suits – with Erika and little brother Fletcher, two, in January.
Further fundraising events to help pay for future sessions – which each cost between £8,000 and £9,000 for therapy and accommodation – are also in the pipeline.


Dad Jamie, 28, said: "When we started fundraising we never in our wildest dreams thought we would raise so much so quickly.
"It's fantastic we can pay for treatment for the next few years, our biggest worry is what we will do when the £106,000 runs out.


"We're hoping to organise two fundraising events in 2009 but don't want to keep asking the same people for help.
"It is tough on all of us when I'm playing rugby and we're apart, but it's worth it to help Brennan.
"Every day he does something different and to see those things is amazing, even a little improvement is better than nothing.


"We just have to take every day as it comes."