In Touch magazine has learned One Direction singer Louis Tomlinson demanded a DNA test as soon as his son, Freddie, with ex-fling Briana Jungwirth was born.

"He wanted proof the baby was his,” a source explains. “Louis had the test done as soon as the baby was born.”

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The test revealed that Louis, 24, is in fact the father (as In Touch previously reported, Briana, 23, was seeing another guy in the music industry at the time of their fling).

For more on this and all your favorite celebrities, pick up the latest issue of In Touch magazine, on newsstands now!