Taylor Swift “can’t imagine” her life without Selena Gomez.

The ‘Bad Blood’ hitmaker captioned the picture, which was shared on her Instagram account, with the caption: “Going through old pictures today, because @selenagomez just turned 24!

I can't imagine my life without you, Selena. HAPPY BIRTHDAY! (sic).”

And instead of receiving extravagant gifts, the ‘Kill ‘Em With Kindness’ hitmaker has asked for fans to celebrate her special day by donating to charity, which will help to prevent a cure for Lupus disease.

The former ‘Wizards of Waverly Place’ actress – who was diagnosed with the auto-immune disease - tweeted: “I asked all my friends and family to make a donation for my birthday. If you want to, would love you for to join http://www.lupusresearch.org/donations/ (sic).”

Meanwhile, Selena has also credited the blonde star as one of her closest pals.

Speaking previously about her intimate friendship group, she said: “I can count on one hand the people I could call and who would be there for me.

"Taylor is one of the greatest people. When I split with my first boyfriend and I was really sad about it, she flew into town with homemade cookies and a bunch of junk food. To this day, if I called her, she would do the same thing, despite being one of the busiest people in the world."

And the duo have proved nothing can break their tight bond when footage leaked of Taylor’s phone call with rapper Kanye West over his ‘Famous’ track, which has the lyrics “I feel like me and Taylor might still have sex/ I made that b***h famous”.

Selena jumped to Taylor’s defence and shared her views on the feud via social media. Speaking previously she said: “There are more important things to talk about… Why can't people use their voice for something that f***ing matters?

"Truth is, last thing we need right now is hate, in any form. This industry is so disappointing yet the most influential smh.(sic)."