UPDATE (9/3/2013): A source tells Us Weekly that Pippa Middleton is not engaged. Guess we'll have to wait a bit longer for that semi-royal wedding!

Original story (9/1/2013):

Pippa Middleton appears to be good at keeping a secret, as it now looks like she is already engaged!

Pippa, 29, and stockbroker boyfriend Nico Jackson, 35, are reportedly secretly engaged, according to the Mirror. Pippa's big sister, Kate Middleton, 31, gave birth to baby George on July 22.

The couple's friends have revealed that the two apparently got engaged shortly before this summer's Wimbledon tennis tournament. They are said to be formally announcing the engagement after Pippa's 30th birthday next Friday. 

"Pippa loved seeing Kate go down the aisle, and now it is her turn for a ­fairytale wedding," says a source. "She couldn’t be more sure that Nico is the right man for her."

"They are such a good fit for each other, and their families get on really well," adds an insider. "Everyone is so happy for Pippa." We are, too!

Word has it that Pippa is currently designing her ring and planning to throw a reception at her parents' pad in Berkshire, England. The couple is reportedly hoping to marry next spring. 

Congrats to the happy couple!

Source: Mirror, Us Weekly