Alexis Bledel's former co-star Lauren Graham is ''very happy'' she is engaged.

The 46-year-old actress who starred alongside Alexis, 31, on the 'Gilmore Girls' for seven years until 2007 is thrilled she is set to tie the knot with her 'Mad Men' co-star Vincent Kartheiser.

The 'Parenthood' star told 'Entertainment Tonight' reporter Jarrett Wieselman on Twitter: ''Yes! Very happy for them. Two gorgeous and talented people'', after he wrote: ''Time flies, right?''

A source told that Vincent proposed to Alexis '' a few weeks ago'' with a ''huge'' ring.

Another friend said: ''They couldn't be happier.''

The couple started dating after falling for each other on the set of advertising drama 'Mad Men' last year when Alexis joined the cast as Beth Dawes for a short stint.

A source previously said: ''Vinnie basically fell in love with Alexis while she filmed a three-episode cameo. He was definitely smitten with her from the beginning.''

When she was working on 'Mad Men', Alexis had nothing but praise for Vincent.

She said at the time: ''He's light and funny and has lots of energy on set. He keeps everybody energised as well.''