The 21-year-old singer made a move on Danielle Deleasa whilst on holiday in the Bahamas, but she took more of a shine to his sibling.
He told Details magazine, 'Actually, I hit on her first. And after that she and Kevin hit it off, of course.
'Now we have a fourth person travelling with us everywhere [on tour], so that's a different thing completely.'
Jonas admitted that he has had his heart broken in the past, but said things with current girlfriend Ashley Greene are going from strength to strength.
Talking about his lost love, he said, 'I won't say her name, but I was in a relationship, and we tried to work things out, and she, you know, I was really upset because she broke up with me.
'I think what works about it with Ashley is she really puts my feelings first. She understands my busy schedule. She'll fly out to my shows. She's been to places in South America that I can't even pronounce.'