Selena Gomez to be a big sister

Selena Gomez's mom had a double reason to celebrate Mother's Day on Sunday (12May13) - she is expecting a baby.

The 20-year-old star shared the news with fans over the weekend by posting a photo of herself cradling mom Mandy Teefey's bulging belly in celebration of the holiday.

In the accompanying caption, she wrote, "Hope all the amazing moms had a great day! I have the best momma in the world. I love you so much!"

Teefey's pregnancy news comes less than two years after she suffered a miscarriage in December, 2011. The child will be Teefey's first with her second husband Brian.

Gomez's mom divorced the singer/actress' father, Ricardo, when she was just five years old.