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 Lupus

and her mother Mandy Teefey admits it was one of the toughest things to experience as a parent.

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

Meanwhile, Selena previously admitted she faced a "life-or-death" situation

prior to her kidney transplant last year – we just hope it’s all better now!