Beyoncé's mother Tina Knowles ''can't wait'' for the star to give birth.

The 35-year-old pop megastar is due to welcome twins into the world later this year with her husband and rapper Jay Z - with whom she already has five-year-old daughter Blue Ivy - and the star's mother has expressed her excitement at becoming and grandmother yet again.

She said: ''I'm so excited. I can't wait.''

And 63-year-old Tina - who is also mother to 30-year-old singer Solange Knowles - has also praised her eldest daughter for being an ''incredible parent''.

Speaking to People magazine at the Inaugural Wearable Art Gala, Tina said: ''[Beyoncé and Jay Z are] incredible parents. She's a really good mom. Really patient and kind.

''[My biggest lesson was] teaching them that what is on the inside counts more than what's on the outside. I see her passing it on, and it makes me really proud because that was my biggest lesson.''

Meanwhile, Tina recently claimed she was in the dark about the gender of her daughter's unborn duo, as she said she was ''so excited'' for their birth in the next few months.

She said when asked about the gender of her grandchildren: ''I would be happy with whatever God gives me. It's the biggest blessing. I'm so excited!''

Although Beyoncé - who announced her pregnancy back in February - is due to give birth fairly soon, the brunette beauty certainly isn't showing any signs of slowing down as she and Jay Z - who got married in 2008 - are trying to buy a 123-room mansion to accommodate their growing family.

The couple secretly viewed an £85 million Hollywood abode belonging to heiress Petra Stunt and her businessman husband James Stunt in February.

A source said: ''Beyonce and Jay Z are actively hunting for a house, something they can settle in for the next decade or so, and Petra's place seems to be very appealing to them. They were shown around two weeks ago and are thinking about whether it works for them. They know with their expanding brood it's time to get serious about laying some roots, and having a statement pad in Hollywood is at the top of their list.

''They loved the space and the size, they just need to work out if it's the right fit for the future.''