updated 08/17/2011 AT 5:00 PM ET
•originally published 08/17/2011 AT 2:55 PM ET
David Cross and his longtime girlfriend, Amber Tamblyn, are engaged to be married, her rep confirms to PEOPLE.
The actress, 28 – who starred in General Hospital and Joan of Arcadia before moving on to the big screen in the 2005 hit The Sisterhood of the Traveling Pants – recently returned to TV with a role on House.
Cross, 47, is perhaps best known for his outrageousness on the 2003-06 cult sitcom Arrested Development, on which he played the gaffe-prone, madcap Tobias Fünke. Talk of a feature movie based on the show has long been circulating. Currently, he stars in the British-American comedy TV series The Increasingly Poor Decisions of Todd Margaret.