"I came to my trailer one day before the baby was born and there's this little bag and there's like two pregnancy tank tops and a cardigan. I'm like who's this from? Jack Nicholson! He went to a maternity store on his day off and got me maternity clothes!" Actress Kathryn Hahn was surprised to receive the thoughtful gifts from her HOW DO YOU KNOW co-star, Hollywood icon JACK NICHOLSON.