 Maggie is the youngest child of Marge and Homer , and sister to Bart and Lisa . She is often seen sucking on her red pacifier and , when she walks , she trips over her clothing and falls on her face ( this running gag is used much more in earlier seasons ) . Being an infant , she cannot talk . She is a counterpart to Lisa Simpson . However , she did appear to talk in the first Tracy Ullman short . Therefore , she is the least seen and heard member of the Simpson family . 
