Happy Birthday, Sandra Bullock!

One of our favorite stars, Sandra Annette Bullock, turns 45 today.

She's been around for many years, starring in successful hits such as Speed, While You Were Sleeping, Miss Congeniality and Crash, which received critical acclaim.

Just last year, Bullock starred in the most commercially successful films of her career, The Proposal and The Blind Side, winning an Academy Award for the latter.

She's a great actress, but that's not why we love her.

From her handling of the Jesse James cheating scandal to her efforts to help the Gulf Coast, to her sincere, laid-back demeanor, she is truly America's Sweetheart.

Click to enlarge the Sandra Bullock pictures that we put together in this little tribute below and leave a comment with your birthday greetings for the actress ...