NAOMI Watts and her boyfriend, Liev Schreiber, have decided they don't want their unborn child to be illegitimate. The couple once planned to marry after their first child is born. But now Watts wants to tie the knot with Schreiber, 39, before she gives birth in late summer. "There's not enough time to plan a big wedding," an insider told In Touch. "They'll have just 25 guests for the nuptials in her hometown of Sydney, Australia, with a lavish wedding reception for all their stateside friends after the baby is born." Watts' rep declined comment.