LOS ANGELES-Britney Spears is ''grateful'' for her long career. The 37-year-old singer has honoured the 20th anniversary of her debut album '...Baby One More Time' and admitted the past two decades have seen her embark on the ''journey of a lifetime''. She shared a photo of the album cover on Instagram and wrote: ''It's definitely been the journey of a lifetime, full of ups and downs, but I'm grateful for every single moment of it all.''

The 'Slumber Party' singer went on to thank her loyal fans for their support over the years.

She added: ''Getting to know you all over the years has been such an incredible experience, and has made this all worth it. Thank you for your support from 20 years ago, all the way to today.

 I am blessed [heart emoji] 20yearsofBritney '' The heartfelt message prompted a reply from Britney's boyfriend, Sam Asghari. He commented: ''This humbles me! Always blessed. Look where gratitude has gotten you.'' The 'Toxic' hitmaker's musical milestone comes shortly after she revealed she's going on indefinite hiatus due to her father, Jamie Spears', ill health.

She has has put her 'Britney: Domination' run at the Park MGM resort in Las Vegas on hold until further notice in order to spend time with her dad.

Britney - who has kids Jayden, 12, and Sean Preston, 13, with ex-husband Kevin Federline - explained: ''I am dedicating my focus and energy to care for my family. We have a very special relationship and I want to be with my family at this time just like they have always been there for me.

Jamie became seriously ill two months ago, when his colon spontaneously ruptured and he was required to undergo surgery.

He subsequently spent the next 28 days in the hospital, and members of the Spears family have thanked the doctors, nurses and staff at the hospital for saving his life.