Jamie Lynn Spears Describes Britney's Behavior as 'Erratic, Paranoid, Spiraling'

Jamie Lynn Spears describes Britney Spears' behavior as "erratic, paranoid and spiraling" in her new memoir.

The 30-year-old younger Spears sibling opened up about her relationship with her famous sister and her controversial conservatorship in an interview with Good Morning America today.

"I felt like she was another momma," Jamie Lynn Spears told ABC's Juju Chang who went on to say that the Zoey 101 star noticed her sister's behavior change as she got older.

"Jamie Lynn says that as the years passed, she noticed Britney's behavior begin to change," Chang said, adding: "Your words to describe her behavior over your lifetime was 'erratic, paranoid and spiraling.'"

Chang then asked Spears: "How do you see your sister's state of mind currently?

Jamie Lynn responded: "I can't really speak to anyone else's state of mind, I don't think that's fair. But I'm allowed to say how I felt because that matters and it matters that I was in pain."

The Zoey 101 star is releasing a book titled "Things I Should Have Said."

Jamie Lynn Spears
Jamie Lynn Spears speaks to Juju Chang on Good Morning America. ABC

On the subject of her sister's conservatorship, Jamie Lynn Spears said she didn't really understand it and that she was a pregnant teen when it started.

"I was happy. First off, I don't understand–when it was put into place, I was a 17-year-old, I was about to have a baby," Jamie Lynn Spears said.

"So I didn't understand what was happening, nor was I focused on that. I was focused on the fact that I was a 17 year old about to have a baby. I understand just as little about it then as I do now."

The conservatorship ended in November after 13 years and Jamie Lynn Spears' involvement has long been questioned by the pop star's fans.

Today she defended her role in the arrangement and said that she helped her big sister with resources to end the conservatorship.

Jamie Lynn Spears, Britney Spears
Jamie Lynn Spears, Britney Spears Getty Images

"I've always been my sister's biggest supporter," Spears told Chang. "So when she needed help, I set up ways to do, went out of my way to make sure that she had the contacts she needed to possibly go ahead and end this conservatorship and just end this all for our family. If it's going to cause this much discord, why continue it?"

When asked if she agreed with the conservatorship, she responded: "It wasn't about agreeing with the conservatorship, everyone has a voice and it should be heard.

So if she wanted to talk to other people, then I did, I set that up. I even spoke to her legal team, who I—her legal team, previous legal team, and that did not end well in my favor. So I did take the steps to help, but how many times can I take the steps without, you know, she has to walk through the door."