The Transformers star, 41, shared this hilarious photo of Axl dressed in a blue and white sailor outfit, explaining, "He just turned one! He's like, 'I love the paparazzi!'"
Duhamel also revealed that prior to giving birth to Axl, his wife Fergie had actually never held a baby before.
... Yes, you read that right.
"I had two younger sisters, so I had a lot of practice growing up," he said about changing diapers. "She had never held a baby before having our little guy. ... I don't think she had really ever held a baby, especially a baby brand-new, before we had ours."
Though clearly, instinct took over, as he now calls her a "professional."