Spears sisterhood in crisis

Jamie Lynn paints a tragic family portrait in memoir amid Britney feud

A “paranoid and erratic” Britney Spears once wielded a knife and locked herself in a room with younger sister Jamie Lynn Spears, according to the latter’s new memoir.

The frightening incident — which the younger Spears details in “Things I Should Have Said,” out this week — supposedly occurred in the aftermath of Britney’s quickie marriage to childhood friend Jason Alexander, and their subsequent annulment less than three days later, in 2004.

“[Britney] said to me, ‘Baby, I’m scared,’ and took a large knife from the

kitchen, pulled me along to my room, and she locked us both inside,” Jamie Lynn, 30, writes. “She put the knife in the bedside table drawer and simply repeated, ‘I’m scared.’ She needed me to sleep beside her . . . I knew something was very wrong, and I was powerless to do anything about it.”

Britney, 40, denied the allegation in a Twitter post: “I’ve never been around you ever with a knife or would I ever even think to do such !!!” she wrote, addressing Jamie Lynn directly.

“Things I Should Have Said” arrives amid a very public feud between the sisters. It started during the #FreeBritney movement as Spears sought to end her conservatorship, and has continued through the subsequent end of the 13-year legal arrangement — which also has seen Britney warring with father Jamie. Suffice it to say, the family dynamic has seemed “Toxic.”

Once ‘like second mother’

Things weren’t always so strained between Britney and Jamie Lynn. In fact, the actress writes that during her childhood, her older sister “became like a second mother to me. She was considerably older than I was, and she adored having the role of caregiver. Momma was wonderful, but my sister treated me like I was her very own American Girl doll.”

Jamie Lynn says that the pop super

star encouraged and supported her own career as an actress, while fiercely protecting her. Britney even intervened on the set of “Zoey 101” — the early 2000s Nickelodeon sitcom that starred Jamie Lynn — when she was having issues with co-star Alexa Nikolas.

“A very pregnant Britney came to the set to visit and have a chat with Alexa,” she writes. “Britney didn’t waste any time getting to the point. ‘Are you making fun of my sister? Telling lies and spreading rumors? You shouldn’t do that!’ Britney told her that she wouldn’t keep jobs if she continued to treat people that way. Alexa scurried away from the trailer.” But the sisters grew up in a tumultuous home, with their dad Jamie’s drinking — “a lot and often,” writes Jamie Lynn — and their mother, Lynne, not doing enough to protect them from it.

Jamie Lynn writes that she was at the center of family drama before she was born: She was an “oops” — her word — after her dad had a vasectomy but then forgot to go for a post-op checkup to make sure the procedure had worked. After Lynne found out she was pregnant with Jamie Lynn, “Momma didn’t talk to him for days, and she stayed mad for weeks.”

Their mother also always made it clear that Britney’s career was the most important thing in the family, which Jamie Lynn came to resent.

“I was taught to defer to Britney or behave in a way that made things easier for her,” she writes. “Momma said stuff like, ‘Come on, Jamie Lynn, we don’t want to upset your sister.’ . . . What complicated things even more was that Momma reveled in the attention that came with being Britney’s mother.”

Still, Jamie Lynn stood by her sister, until Britney started behaving erratically after splitting up with Justin Timberlake in 2002. She writes that “Britney was looking to party away the pain of her breakup.”

Jamie Lynn took the breakup hard, too: “I adored Justin. He wasn’t just my sister’s boyfriend . . . Justin was always so sweet to me, and his relationship with Britney was the only one in my life that gave me a sense of stability . . . from my perspective, they adored each other and made me a part of their relationship in the best of ways.”

Things only got worse for Britney when she reconnected with Alexander in the aftermath of the breakup. They would eventually go off to Las Vegas together for New Year’s Eve in 2003.

“I just knew this was a bad idea. Something was way off with her,” writes Spears. “The last thing I said before she left was, ‘Now don’t go and marry Jason while you’re there, Britney!’ She rolled her eyes at me and said the equivalent of ‘as if.’ But sure enough, within hours we got word that in a haze of substance she had married him.”

Tying the knot just four hours into 2004, Britney and Alexander didn’t stay married for long — all of 55 hours — after her parents forced them to get an annulment. “The marriage had ended within hours,” Jamie Lynn writes, “but the chaos of my sister’s life was just beginning.”

Secret-pregnancy strain

As Britney’s controversies swirled, the sisters drifted apart. When Jamie Lynn became pregnant at 16 with daughter Maddie, she wasn’t even allowed to tell Britney.

“[My team] went so far as hiding my pregnancy from my sister, claiming, ‘It’s too risky to tell Britney about the baby,’ ” she writes. “I needed her more than ever, and she wasn’t able to help me in my most vulnerable time. Britney’s condition was spiraling into something more concerning. They were concerned her instability at that time made her untrustworthy.”

Britney would eventually find out about the pregnancy through an article in the press. “To this day, the hurt of not being able to tell my sister myself lingers,” Jamie writes.

When Britney’s conservatorship started in 2008, the younger sister believed that it was the right decision. “Britney’s behavior became more unstable until it all came to a head,” she writes. “With the support of my parents, Britney got the help she needed.”

For a time, the conservatorship helped Britney and her dad bond. “They stayed sober together, and seeing my father put Britney’s needs ahead of his own desires helped my old resentments fade,” writes Jamie Lynn. “For a period of time, the conservatorship mandated that Britney be drug and alcohol tested on a regular basis. My father volunteered to do it with her in solidarity.”

Now that family solidarity seems to be missing.

“We are supposed to have each other’s back,” Britney tweeted about Jamie Lynn on Saturday.

Still, there may still be hope yet for the sisters, with Britney also tweeting that, “All I know is I love you unconditionally.”