"The first time you've got an IV drip in and oxygen, and they monitor to make sure there's no major reaction," Mr Caldwell said.
"When he was stung in January his eyes were swollen and he had a blocked airway. To go from that to two in one day is amazing."
Mr Caldwell said the Star Wars event had taken the pressure off the kids during a treatment that was "quite scary" for them.
Mr Caldwell said the treatment would continue via Tamati's GP for the next four to five years and he would still need to carry an Epipen, though the risk of a severe reaction would be greatly reduced.
Epipens (auto-injectors for the emergency treatment of life-threatening allergic reactions) are not publicly funded, cost about $120 and need to be replaced each year.
Young patient Todd Yendell came up with the May the 4th idea.
Paediatrician Dr Andre Schultz said each child was embarking on a five-year treatment - "a major undertaking".
On day one the patients receive five injections of bee venom, three the next day, two injections on day eight, one injection on day 15 and then one injection on day 29.
After this time they visit their GP once a month for an injection, for five years.