The 38-year-old singer's son with actor-model Josh Duhamel, Axl, tries to chime in when his mother sings, reported Contactmusic.
"When I sing, he'll look at me and laugh and try to chime in. He makes the funniest sounds. He gets very proud of himself," she said.
Josh, 41, and Fergie have temporarily relocated to Austin, Texas and is happy they can be together while he is shooting for his new movie 'Lost in the Sun'.