"Boruto's Birthday" (ボルトの誕生日, Boruto no Tanjōbi) is episode 51 of the Boruto: Naruto Next Generations anime.
A group of thieves is attacked in an abandoned mine tunnel after robbing the Thunder Train. After a mission, Boruto offers to eat with his team mates, and Team 7 overhears other genin gossiping about them. This gets under Boruto's skin, who goes off on his own. Boruto thinks back to his last birthday. Sakura, Sarada, and Mitsuki showed up, but Naruto didn't. Boruto was frustrated, but tried to hide it. Naruto arrives home after Boruto's gone to bed, and is sad that even though he got Boruto a present, he doesn't know what games his son likes. Boruto goes to the Scientific Ninja Tool Research Centre instead of home. Boruto vents his frustrations to Katasuke while he works on the Kote. Katasuke gives Boruto a Scientific Ninja Tool for his birthday. Boruto arrives home, and sees Himawari marking the calendar. She says it's to give their father advanced notice of her upcoming birthday. Himawari is sad at the idea of Naruto missing her birthday. Boruto promises her he won't let Naruto miss it. The next day, Team 7 is assigned to find the Thunder Train thieves. Boruto is concerned that if it's not a big mission, people won't acknowledge him, and continue to measure him by Naruto's standards. Shikamaru informs Naruto that another ruin related to Kaguya has been discovered, Naruto wishing to check on it himself. Boruto and Naruto cross paths on their way out. Naruto apologises for missing Boruto's birthday, but Boruto dismisses it, telling Naruto not to miss Himawari's instead. Team 7 arrives at the town near the border of the Land of Fire, and discover that one of the robbers came out of the mines traumatised, claiming his accomplices were killed by a monster. The robber's claim that a "white one" is coming for them picks Konohamaru's interest. In the tunnels, they find the thieves' corpses, and footprints. They follow the footprints further inside, passing by an Ōtsutsuki clan carving. They reach the end of the footprints, and realise it's a trap. They are attacked by a giant, multi-faced White Zetsu.
- Naruto mistakenly says it has been ten years since the Fourth Shinobi World War when it's confirmed that fifteen years have passed since the end of the war. Also present in the English dub.