Fergie's 11-month-old surprised her when he began to start walking, but poor old dad Josh Duhamel was busy at work and missed his son finding his feet.
Speaking to Us Weekly, Fergie recalled the moment Axl took his first steps.
She said: "He just had his first steps [on] August 12... I was shocked! He climbed up the stairs and he climbed back down. I was helping him back down and he got up the stairs and he [stretched out his arms] and came to me!
"It was exhilarating! I just thought, 'Did my son just walk?'"
But despite being over the moon for her little one, Fergie couldn't help but feel guilty husband Josh had missed it.
"He was at work. I felt so bad! But you know, we're both working parents so each of us are going to get different gifts", she said.
He might of missed this moment in Axl's life, but Josh has made sure to capture most of his boy's highlights since he was born.
From his first World Cup, to his first Super Bowl on which Axl gave a very cute review and his first time dressed up for the Oscars, daddy Josh has had it covered.
Safe Haven actor Josh and Fergie welcomed their son Axl back in August last year. The couple married back in 2009 after five years of dating.
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