‘Avengers: Endgame’ Confirms That RDJ’s Tony Stark Is Adopted

Fans of the MCU know all about Tony Stark’s (Robert Downey Jr.) complicated relationship with his father, Howard Stark. Both were genius, billionaire, playboy philanthropists, but with those similarities came a lot of resentment and anger.

'Avengers: Endgame' was reportedly RDJ's last outing as Tony Stark
Robert Downey Jr. | Photo by Alberto E. Rodriguez/Getty Images

For most of his life, Tony lived in Howard’s shadow, but that all changed when he became Iron Man. Still, their relationship didn’t end well in Captain America: Civil War and Tony’s last words to his father haunted him for years. But, when Tony got the chance to see his dad when he traveled back to 1970 during Avengers: Endgame, he was able to tell him (in a roundabout way) that he loves and forgives him.

However, there was one more thing that happened during that moment of closure – fans found out that Tony Stark isn’t Howard Stark’s biological child.

Flowers and sauerkraut

In Avengers: Endgame, Tony Stark and Steve Rogers travel back to S.H.I.E.L.D. headquarters at Camp Lehigh in 1970 to get their hands on the Space Stone and more Pym Particles. While Tony and Steve are back in time, Steve gets to see Peggy Carter, and Tony runs into his dad.

Tony and Howard even have a brief conversation, and this is where fans get a major hint that Howard and Maria Stark adopted Tony.

Thanks to The Avengers we know that Tony’s S.H.I.E.L.D. file gives his date of birth as May 29th, 1970. But, in Endgame Tony and Steve travel to April, 7th, 1970, weeks before Tony’s birth.


Tony ends up talking to Howard in the elevator, and Howard explains that the flowers and sauerkraut he is carrying is because his wife is expecting, and he spends too much time at the office.

According to Screen Rant, Tony Stark’s reaction to this statement is revealing.

How far along?

After Howard gives his explanation for the flowers and sauerkraut, Tony immediately asks Howard how far along his wife is in her pregnancy. His dad doesn’t answer the question, but why would Tony ask in the first place?

Tony knew he was going back to 1970 – the year of his birth – so, why did the flowers and sauerkraut confuse him? Was this something that Howard only did when his wife was in the hospital ready to give birth?

The best explanation to all of this is that Tony Stark realized during his conversation with his father that he is adopted.

Just like the comic books

Fans of Marvel comic books know that Marie Stark gave birth to a son who was born with a degenerative condition. During Marie’s pregnancy, Howard went to alien robot Rigellian Recorder 451 for help, and 451 agreed to help the baby survive only if he could bioengineer the child.

The goal of the bioengineering was for Howard’s son to help humanity accelerate their technology and to protect Earth from extraterrestrial threats. Howard agreed to 451’s terms but later discovered that the robot had hidden a kill switch that was a threat to his son.

To interfere with the kill switch, Howard secretly developed a “bio-cocktail,” but his interference caused his son to become fatally ill. At that point, Howard and Marie hid their baby in Maria Stark Foundation Hospice, but they couldn’t have another baby because of the risk of 451 finding out that Howard interfered with his bioengineering.

Instead, Howard and Marie adopt a healthy son they named Tony Stark.

Tony Stark’s parents never told him the truth

In the Iron Man comics, Howard and Marie never tell Tony the truth about his adoption, and it appears with this one simple conversation in Endgame that the same thing happened in the MCU. Of course, the movie never told the story of the biological son, the alien engineering, and the substitution. Endgame seems to be pointing to the adoption part of the story.

Tony Stark knew his father was working with Hank Pym before he was born, which is why he came up with the idea for him and Steve to go back to that point in time.


But, why not go back to his exact birthday when he knew for a fact that Harold and Hank were working together? Why weeks in advance?

It looks like that was Marvel’s way of acknowledging that Tony may not know his real birthday because he is not Howard and Marie’s biological son, even though most people in the audience didn’t realize the subtle hint.