Selena Gomez's health battle was the ''hardest thing'' for her mom to ever experience.

The 'Bad Liar' hitmaker had to undergo a kidney transplant last year to help with her ongoing

battle with autoimmune disease Lupus and her mother Mandy Teefey admits it was one of the toughest things to experience as a parent.

She said: ''That was probably one of the hardest things to ever experience as a parent, and especially when there were complications, and it was just me and her, and she had to go in.''

And Mandy was not only concerned for the 25-year-old singer but also for her friend Francia Raisa, who donated the kidney.

In a Facebook Live with Entertainment Tonight, she added: ''I was not only carrying the weight first as the mother, but I also felt the weight for Francia and her mother and her family. I think I'm banned from Cedars. I went to both sides of the towers. For some reason they were in different towers, and every little thing, I was monitoring, like, yelling and freaking out. It was pretty rough. God bless any of the families that have kids with ongoing illnesses because the strength that those families have is insane.''

Meanwhile, Selena previously admitted she faced a ''life-or-death'' situation prior to her kidney transplant last year.

She said: ''I am really honoured to be here with all of you guys tonight, my lupus community. As many of you know, or might now know, I was diagnosed with lupus about five or six years ago. I've been speaking out about my situation to raise awareness about the disease. After undergoing so many tests to monitor my kidneys my doctors told me I have lupus nephritis, one of those complications from lupus. They said I would be needing a kidney transplant. Maybe I wasn't necessarily really good at knowing what that meant so it actually got to a point where it was life-or-death. Thankfully, one of my best friends gave me her kidney and it was the ultimate gift of life. And I am doing quite well now.''