The Jonas Brothers' breakup didn't stop Joe from gushing about his new niece and Kevin's daughter, Alena Rose.

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"She's so tiny, it kind of scares me. She was awake, kicking and smiling and grabbing for your finger," Joe told E! News at the G-Star Raw X Bionic event in New York City Saturday.

Joe confessed that it's "mind blowing" and "exciting" to have a new member of the family, especially a little girl.

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"I honestly can't wait to spend more time with her."

He also gave an update on how new parents, Kevin and his wife Danielle, are doing.

"I mean [Kevin] is a dad now and it's kinda crazy. I know he has not gotten much sleep. He instagrammed a picture at like 2 p.m. saying 'good morning' with the baby so he was probably up all night with her as she was crying."

While the brothers announced their shocking decision to end The Jonas Brothers late last year, Joe confessed that becoming an uncle for the first time has brought them closer.

"I don't want to sound cheesy saying that but you just want to spend more time with each other and you're just excited for the next chapter of each other's lives."

As far as if Joe is itching to become a father now that he has a niece to swoon over, that's another story.

"I will take my time. I will take my time with running around and having my fun. Down the road."

Danielle gave birth to Alena Rose on Feb. 2. Kevin announced the news via Twitter and gave his followers a play-by-play and lots of updates on when Danielle went to labor and when the baby girl arrived.