Look Who's Talking 4
They should do a new movie where Mikey, now grown up, gets a girl pregnant in a one night stand. She leaves him with the baby nine months later (voiced by Bruce Willis) and now Mikey has to go through what his mother did when he was born and find love, and a mother for his child, J.J. (named after John Travolta's character from the original trilogy).
I doubt they could get Travolta back for this, but they could throw in a cameo from Kirstie Alley and cast David Gallagher as Mikey, since he played the part in the last movie.
Why don't Kennedy's make good boxers? None of them can take a shot to the head