Britney Spears' loved ones show their support after she checks into mental health facility

Britney Spears' loved ones are standing firmly behind her after news broke that the singer has checked herself into a mental health facility.

Spears' younger sister, Jamie Lynn, took to Instagram on Wednesday to share a throwback photo, making her big sister her #WCW (Woman Crush Wednesday) this week. The picture adorably shows Jamie Lynn getting off the bus with Britney on her first day of school.

"Yup, she rode the bus home with me after my first day of school, cuz she’s the fn best #WCW," she captioned the post.

The "Toxic" hitmaker's boyfriend of about two years, Sam Asghari, also shared his love for Britney on Instagram following the news, reposting her inspirational quote -- "Fall in love with taking care of yourself, min, body, spirit" -- and adding his own caption.

"It isn’t weakness, It’s a sign of absolute strength, people should only be inspired by this, at least I am," he wrote.

Meanwhile, Britney's ex-husband, Kevin Federline, also released a statement to ET showing his support, despite their recent battle over child support.

"Kevin commends Britney for recognizing that she needs to take a step back and that she is taking the reasonable steps to dealing with her situation in a responsible way," Federline said through his lawyer, Mark Vincent Kaplan. "He wishes everyone well."

The former couple's sons, Sean Preston, 13, and Jayden James, 12, "are in the full-time care of their dad" as their mother seeks help for her mental health, Us Weekly reports. Britney and Kevin were married from 2004 until 2007.

Britney sought help this week after realizing that her struggle with her father, Jamie's, worsening health was taking a huge toll on her own wellbeing. Her father has been dealing with severe colon issues since October and has had two surgeries since.

"She seems to be on a constant roller coaster and can't get off. She is finally getting the help she needs," an insider explained to ET. "She is the one who finally decided she needed help and made the decision to manage her own emotions. She finally realized it was affecting her everyday life and even her relationships. She wants to feel better and more relaxed and taking time to focus on herself truly is her only option. It has been a rough year. While those closest to her have encouraged her to get help, she finally decided on her own it was time."

Another source told the outlet that Britney has been "truly isolating herself" from the outside world and has grown even more protective of her two sons. "Her father's illness has frightened her," which caused her to worry more about them and less on herself.

"She has had little communication to the outside world and spends most of her time with the staff and kids," the source explained. "She's truly isolating herself. She is painfully protective of her children and doesn't trust anyone with them. She worries constantly about them. The children are doing fine. She loves them so much and tries so hard with them."

Insiders told People that Britney is at an "all-encompassing wellness treatment" facility, where she'll remain for several weeks.

"Britney just needed to focus on herself," one insider explained. "Her dad being sick has taken a toll on her. He nearly died and actually had another surgery a few weeks ago. He’s not doing well. They’re so close and it has been a lot. There is nothing dramatic going on with her -- she just realized she needs to make sure to take time to care for herself."