Rihanna sings Happy Birthday to Chris Brown amid Karrueche Tran's restraining order against singer

Chris Brown celebrated his 28th birthday on Friday (5 May) and according to reports, he received a surprising phone call from his ex-girlfriend Rihanna. The songstress reportedly face-timed with her ex and wished him by singing Happy Birthday.

"Rih was not about to let this day go by without hitting Chris up on his birthday. They FaceTimed and when he picked up she immediately started singing him happy birthday. He was speechless," a source told Hollywood Life.

The brief chat between the ex-lovers left the Loyal singer with a big smile as RiRi concluded the birthday wish with "I love you''. "His eyes lit up and he had the biggest smile on his face. He was bobbing his head when she was singing and when she was done he was like wow. They talked briefly and she told him I love you," the source added.

Last month, Brown sent birthday wishes to Rihanna's mother Monica Braithwaite and it sparked the estranged couple's reunion rumours.

While the former exes are turning into friends, Brown's relationship with his other ex Karrueche Tran is turning sour as the American model's birthday present has left him furious. Tran's representative handed over the legal restraining order to the singer as he was seen outside of a Houston nightclub on 4 May after celebrating his birthday party. TMZ reports that Brown was miffed after receiving the legal documents on his birthday.

Tran filed a case against the Royalty singer in February this year, claiming that Brown has "told a few people that he was going to kill me," and that he had even "punched" her in the stomach and pushed her "down the stairs".