Sienna Miller Shows Baby Bump

Sienna Miller chose to be oysterish about her private life, but now the signs are too obvious for concealment: the actress is engaged and pregnant!

As for her going the family way, her baby bump was very much to the fore when she showed up in Manhattan at the Park Avenue Armory opening reception for W magazine’s “Ever Changing Face of Beauty” exhibit late Tuesday. She wore a tight black halter dress that played up her condition advantageously.

The 30-year-old actress has also been sporting a large diamond and platinum sparkler since last week, clear witness of a proposal from the baby’s father, actor Tom Sturridge, 26.

The British movie couple maintained a healthy relationship for more than a year. Her friends were delighted with her choice, opened up a source to PEOPLE last month. Although Sturridge is a little younger than Miller, “he’s mature and he’s a good guy.”

The source added that their friends were hardly surprised that their relationship had brought about engagement and pregnancy, for they were evidently heading that way.