Kris Jenner has revealed why she can’t treat her grandchildren to quality one-on-one time with her, as she claimed she recently made a ‘mistake’ by taking out her eldest, Mason, for dinner.

The Kardashian matriarch, 68, has 13 grandchildren aged four months to 14 years old, with Kendall Jenner her only remaining child who does not yet have a family of her own.

Kris, whose sister Karen Houghton died last week, said she was deterred from trying to ‘really get to know’ them all as she joked it would take her ‘half a month’ and leave her broke – despite being worth an estimated $200 million.

‘I often say to myself that I really should be the kind of grandmother that takes my grandchild to dinner, like once a month,’ she said at Los Angeles Magazine’s The L.A. Woman Luncheon.

‘Like really get to know your grandchild and see what’s happening in school and all this stuff. And I thought if I did that, that would take half a month, just to go out to dinner with my grandkids.

‘And I am like, nope not going to do that. They’re not getting that out of me.’

Kris said her decision to refrain from taking them out was bolstered by a recent dinner with her daughter Kourtney Kardashian’s eldest son Mason, 14, in which she promised to buy him a car if he avoided drink and drugs before he turns 16.

‘I think I did make a little mistake because I took Mason out to dinner, and I was in a really good mood,’ she recalled. ‘I probably had a vodka or something, I don’t know I wasn’t driving.

‘But we met at dinner because he likes to go have sushi and I was like, “Listen if you don’t drink or do drugs until you’re sixteen, and you can prove it – you know it involves testing and all sorts of stuff – I will buy you a car for your sixteenth birthday.”

‘And he loved that and what I realized that I have to do that 13 times. I’m going broke! Thirteen times.’

Kris, who previously revealed her grandchildren call her ‘Lovey,’ was speaking at the event at The Fairmont Miramar last week.

But despite fearing she will be out of pocket if she treats them all to dinner and promises of cars, the reality star said it makes her ‘happy’ to see them most days.

She said: ‘My little thing at the end of the day when I am getting ready for bed, I say, “how many of my grandkids did I get to see today?” And that’s really a thing I do every single day. I count.

‘And yesterday I was at Kim’s office… and some of my grandchildren came in and they were walking by and I’m like, “Hold on one, two”, trying to count to see how far I get. But it’s like my thing. I love it, makes me very happy.’

Mason is Kourtney’s eldest child with her ex, Scott Disick. They also have daughter Penelope, 11, and son Reign, eight. In November she welcomed her first child with husband Travis Barker, son Rocky.

Kris’ daughter Kim also has four children, all from her marriage to Kanye West. Ten-year-old North – who recently announced her debut rap album – is the oldest, followed by Saint, eight, Chicago, six, and Psalm, four.

Khloe, 39, shares True, five, and Tatum, 19 months, with her ex, Tristan Thompson, while Kylie Jenner, 26, is mom to Stormi, six, and Aire, two, with her ex, Travis Scott.

Rob Kardashian has one child, daughter Dream, seven, with his former partner, Blac Chyna.

Kourtney, Kim, Rob and Khloe’s father is the late Robert Kardashian. Kris went on to marry former Olympic champion Caitlyn Jenner, and they welcomed Kendall and Kylie together.

The momager, who is now dating toyboy Corey Gamble, was not so dismissive of her grandkids when they ‘bombarded’ her in celebration of her 68th birthday back in November.

Khloe shared a video of True, Tatum and Dream paying their grandmother a visit at her $20 million, 16,000-square-foot Hidden Hills mega-mansion.

Khloe said: ‘No way to start Lovey’s birthday then to just bombard her with three little munchkins!’

Kris replied: ‘Love it! This is the best ever! You guys, I was so lonely until you got here.’

The following month she played the doting grandmother when she took True and Dream to the theatre to see Dr Seuss’ How the Grinch Stole Christmas.