The 38-year-old singer and Duhamel welcomed Axl Jack last year, reported Contactmusic.
"He's dad of the year, he's the best partner to have a kid with," Fergie said.
The singer loves spending time with Axl.
"The best part of being a mom is just hanging out with my kid. He's my homie! I'm just listening, talking back with him and trying to teach him words like 'nose' and 'dancing'," she said.
"Daddy is trying to teach him 'ball' and I'm trying to teach him 'dance'," she added.