Star news has learned that HARRY STYLES celebrated his 19th birthday with his cougar ex, CAROLINE FLACK, in London this week.

Hear that, Taylor Swift?

SPX 056294

On Thursday, Harry Styles rang in his last teen year in advance in London’s bouncing Groucho club with an ex-girlfriend… but it’s not the infamous breakup song-writing Taylor Swift, whom he split from just last month.

We’re talking about his other older ex, Caroline Flack, whom he briefly dated until January last year despite their 15-year age difference.

Together, the former couple partied with friends until the cute One Direction boy bander turned 19 today, stirring some-ack!-reconciliation rumors between them.

Check out the new photos of Harry and Caroline HERE.

Do you think the eternally bitter Swifty would react negatively to this news (or worse, include it in her lyrics)?

Photos By PR Photos