Gossip Girl stars Blake Lively and Penn Badgley, whose characters used to date on the hit CW show, have been dating more than a year and a half.

According to reports, they are looking to extend that ... forever!

A close pal of Blake's repors that it is just a matter of time. The couple are expected to announce their engagement sooner rather than later.

Sunday is Badgley's 23rd birthday, and while some speculate they might have something else to celebrate then, others say talk is premature.

Just a little, though.

''I think if November 1 was Blake's birthday, he might have surprised her with a ring,'' quipped the source. ''But my guess is over the holidays.''

No question, Penn Badgley and Blake Lively are a cute couple, and one that likes to keep a low profile as well. They would have our blessing.

Penn and Blake. Dan and Serena. They're hot by any name!