Rachel McAdams was ''really nervous'' about working with kids in 'About Time'.

The 34-year-old actress didn't know what to expect when she was confronted with so many babies in Richard Curtis' new romantic-comedy movie, but she ended up enjoying every minute she spent with the youngsters - even though their cries upset her.

She said: ''You've got to love them. That was so delightful, but when they wanted to go home and they're crying, your heart just breaks.

''I think we had a few that won't turn out to be actors when they grow up. This was probably enough of a traumatic experience for them, but they were all so sweet.

''I was really nervous at first as, you know, you're always told, 'Don't do movies with babies or pets,' but it was great.''

Rachel portrays Domhnall Gleeson's on-screen lover Mary in the motion picture and admits she was keen to play the part as soon as she read the ''heart-warming'' script.

She added to the Daily Mirror newspaper: ''I have loved Richard Curtis' movies for so long, so it's such an honour to be a part of one.

''He has this wonderful way of making you take stock of the lovely things in life and yet there's melancholy too.

''I just fell in love with the script and it was very heart-warming. I also liked my character, Mary.

''I thought she was kind of quirky and shy, plus of course there's a great ensemble cast with Bill Nighy, Domhnall Gleeson and Tom Hollander.''