Tina, who is already a proud granny to Beyonce's sister Solange's seven-year-old son Julez, says she cannot wait to be a grandmother for the second time.
Speaking to US Weekly, Tina said:
"I'm the most excited I can be. This is my second time around, she's going to be an awesome mom!"
Tina then let slip that they already know the sex of Beyonce and Jay-Z's baby - but will be keeping mum until the tot is born in February, saying "I know, but I'm not telling!"
Beyonce's mum said the star had suffered some morning sickness but was now feeling well and keeping busy - she also revealed her pregnancy craving: waffles!
"She had morning sickness, but she's over it and she's doing really good...she's very busy." She added that the baby might 'slow her down' a bit, but insisted: "I think she'll be the same great person she's been."
Tina also had words of praise for her son-in-law Jay-Z: "Jay-Z is going to be an awesome. They are very, very happy and just glowing, and it's great to see."
Aw, what a proud granny!