Last Friday, Rihanna spent her 21st birthday alone and without much fanfare, but that didn’t stop the “Umbrella” star’s allegedly abusive ex-boyfriend, R&B singer Chris Brown, from trying to slither back into Ri-Ri’s good graces.

The “Kiss Kiss” star lavished his “Good Girl Gone Bad” with a diamond bracelet and necklace and an iPod Touch for the milestone b-day, a new tabloid report claims.

“Chris called Rihanna to wish her a happy birthday,” a NY Daily News insider revealed on Monday. “He’s absolutely trying to get back into her good graces. He knows he’s very much in the doghouse right now, and is doing everything he can to show her how sorry he is.”

Even Chris’s momager, Joyce, who reportedly “adores” Rihanna sent over a bouquet of flowers for her big day.