Charlotte Caldwell stepped into Irish soil carrying illegal cannabis oil but was neither challenged nor questioned.
Charlotte, from Castlederg, had travelled with her desperately ill young son Billy and her oldest child Kyle from Los Angeles overnight.
Billy has been prescribed medical cannabis in a bid to keep potentially fatal epileptic seizures under control.
Mum Charlotte had announced through Belfast Live that she would be bringing outlawed cannabis oil into the Republic and that she would declare it at Customs.
But when she did, no challenge was made by officials, no questions were asked and Charlotte and her sons walked through the doors to freedom and the waiting media and supporters.
Charlotte said: "I felt anxious as we left the plane but I knew it was the right thing to do.
"So I stopped at Customs and declared Billys drugs and all we heard from the Customs officials was the words, 'Thank you, you can carry on'.
"It felt like the door was literally being opened to us, it felt like we already have legalised medicinal cannabis, it felt like a victory for common sense."
Billys brother Kyle flew to LA yesterday to help bring the 11-year-old and his mother home to Castlederg.
Charlotte said: "We walked out of Dublin airport and just looked at each other and smiled.
"We had done it but now we are on our way to Northern Ireland and we will have to hold our breath as we drive over the border. If I get a call from the police tomorrow then so be it. I hope not and in all honesty, I feel that won't happen.
"Billy has been through so much recently but it seems like the landscape of Ireland and Northern Ireland has changed because of him and because of what we as a family, with the help of all our supporters, have had to do.
"The time is right for change and change is the right thing to do.
"We are almost home and we will have to go back to LA for treatment in a few weeks' time but we can face that knowing we can feel safe in our own home,in our own country, knowing that saving Billy will not see us landed in jail and separated from him.
"We have all fought hard and we have won the first round and we will keep going until the law is changed for everyone.
"I want all the people who supported us in any way to know how thankful we are. We are exhausted but elated and glad and grateful to be home."
Pat Doherty, MP for West Tyrone, was waiting at Dublin Airport for the family with Dr John Burton.
He said: "Billy is absolutely amazing, there were no problems for them here and they are safely through Customs, it is great news.
"It is great for Billy, the next big assessment is eight to 10 weeks away back in America. The treatment Billy is getting can be given legally here at home as a food supplement."