MIAMI -

A South Florida woman thought she pulled off the perfect birthday surprise for her boyfriend, but little did she know: he was about to propose!

Adrian Santaella told Local 10 his girlfriend of one and a half years, Natasha is very smart at figuring out tricks, so he had to get creative to surprise her with an engagement ring.

He enlisted the help of his mother, who told Natasha she needed help planning a surprise party for her son.

When Natasha brought Adrian to what she thought was his birthday party, his family members were holding a nine foot banner that read "Happy Birthday Adrian!"

Moments after she thought she had him fooled, his family revealed the real banner they were holding... one that said "Will you marry me Natasha?"

After a few excited yells and hugs, Adrian got down on one knee and offered his bride-to-be the ring. Amid her excitement, it took her a little while to realize some of her family members were standing in the crowd too!

Their special moment was recorded by Natasha's sister and posted on YouTube. Another shot by an employeeat Latin House on Sunset Drive was posted on Facebook and shared throughout the country.