The UFC star (33) grew up on Clonmacnoise Road in Crumlin, Dublin 12 – down the street from the birthday girl, May Gleeson.
And McGregor was keen to give the “lovely lady” the party she deserved by celebrating her milestone birthday with her family in The Black Forge Inn, which he bought last year for a reported €2 million before spending a further €1 million on renovations ahead of its reopening in July.
Taking to social media on Thursday, the Dubliner shared some photos with his former neighbour and explained that they had a ball looking at old photographs together.
“Happy 90th birthday May Gleeson,” he began.
“This lovely lady and her family are from my childhood road, Clonmacnoise road, Crumlin, Dublin 12. May is showing me pictures of when I was a child here. Incredible! Thank you May and the Gleeson family!
“We lost all our family childhood photos many years ago so there is not many of me or my family available anymore and that saddens me deeply, so to see some is always a real treat for me.”
Continuing, he said that he constantly has photographers and videographers around his family now because he lost so many photos from his childhood and doesn’t want that to happen again.
“I attribute this as to why I have had a full time photographer and videographer around my family and my own life the last so many years,” the Notorious said.
“It’s the sole reason I was able to do all those documentaries coming up because I was scared I would not have anything at all to look back on in years to come, and before I knew it I had a wealth of content and a story to tell.
“It all worked out in the end I suppose which really shows you everything happens for a reason in this life. This was pre social media / pre YouTube / everything. I had guys document it all.
“Before all that started. The Severe MMA guys and then into my own @claymoreproductions team now. Madness. The Black Forge Inn is some place. I forget nothing.
“Thank you so much May I hope you had a great birthday party at our pub, because I sure did with you,” he added.