Showing off her hot bikini body, Sienna Miller was clearly enjoying herself in the Caribbean sunshine yesterday…and we even caught her smiling, which is almost unheard of.

Sienna is spending some time with her family over the Christmas holidays and, if the rumors are true, she is awaiting the arrival of the new man in her life, her former lover Jude Law.

We’re not sure why she’s getting it on again with Law after he did the dirty on Sienna with his children’s nanny a few years back.

But they do say love is blind…

Check out more pictures of Sienna below…