Britney Spears' pregnant teenage sister is laughing off reports her boyfriend has dumped her over concerns he's not the father of her baby. Casey Aldridge is rumoured to have asked for a paternity test to prove he is the unborn child's father, according to U.S. publication In Touch Weekly. But young Spears' representative insists the story is "completely false". A family friend told In Touch reporters, "Casey doesn't want to be with her until he's sure that he's the father." The report follows unconfirmed rumours that an unnamed TV producer is the father of the baby. But the Spears rep states, "They are still together and he has not asked for a paternity test."