Kris Jenner, mother of the Kardashian sisters - Kim, Khloe, Kourtney, Kendall and Kylie - recently told an Australian radio station that Khloe was her "favourite daughter". Lots of people's first reaction to this might be shock - you can't possibly admit to that! But is having a favourite really all that uncommon?
Nearly 25% of mums, and even more grandparents, admit they have a favourite child, according to a survey by Mumsnet and Gransnet.
Even if they don't claim to have a preferred son or daughter, 20% of mums say their kids think that they do.
So just what makes a favourite child? For some, the preference is gender-related (23% of Mumsnetters with a favourite say the child is their only son, while 15% say it's their only daughter), while for other it's linked to birth order (56% with a favourite say it's their youngest, and 39% of grandparents say it's the eldest).
If, deep down, you do have a favourite but think you've hidden it well, don't be so sure. Of Mumsnet users who confessed they have a favourite, 13% say their other children definitely or probably know about it.
The research also found around half of those who admit to favourites say they think such feelings are "awful", and most believe it's damaging for the other siblings. Many agree it can even hurt the favourite children themselves.
"Favouritism is one of the last taboos and can provoke a lot of guilt, so it's important to say that feeling a greater affinity for a particular child - often, whichever one is willing to put their shoes on - is fairly common and doesn't have to be disastrous, says Mumsnet founder Justine Roberts.
Displaying favouritism, however, can hurt everybody. There can be profound long-term psychological effects of feeling like the less-loved child, and it's not even necessarily a blessing to be the favourite child either, as having it easy may leave you unprepared for real life and possibly even desperate to distance yourself from a clingy parent, among other things.
Yet an unrelenting 50% of Gransnetters and 33% of Mumsnetters with favourites say they aren't ashamed of their feelings.
"Toxic favouritism, where siblings become aware of being treated unfairly over the long-term, is a whole other ball game," warns Roberts. "The distilled Mumsnet wisdom is that lots of parents like their children differently: the crucial thing is to love them all wholly."
So how can parents help ensure favouritism doesn't negatively affect their kids? Mumsnet offers the following eight tips ...
1. Keep it quiet
Don't tell the children, ever.
2. Ask yourself why
Do admit it to yourself and analyse why you feel that way. The research found parents are won over by children being "easy", with 61% saying their favourite's siblings are more tricky or demanding.
Grandparents are less likely to prize this quality - possibly because they spend less time with them - and less than half (41%) say their favourite is the easy one. Instead, a third of grandparents with a favourite say that grandchild reminds them of their own son or daughter at a similar age, and 41% of parents with a favourite say the child reminds them of themselves.
3. Treat them equally
Find ways of parenting different children equitably. This is easier said than done and doesn't mean treating children in exactly the same way as each other (contrary to the beliefs of the children themselves).
4. Have a good time with the less favoured
Find ways of spending quality time with the child you find more difficult, doing things you both enjoy. It's easy to get stuck in a cycle of negativity with a child who's especially challenging. Make a day when just the two of you can be together and then carry on making some one-to-one time after that.
5. Be loving
Physical affection is important: 74% of parents with a favourite say the child is extremely loving and affectionate. Less favoured children may not be so touchy-feely, but that shouldn't stop mums and dads still trying to demonstrate their love. Mumsnet suggests a prickly, unhuggable child may enjoy a head massage, for example.
6. Give it time
Wait and see what happens, as some relationships flower later than others.
7. Don't overcompensate
Don't make such a massive effort to treat your least-favoured child fairly that their siblings think the child you find more difficult is actually your favourite.
8. Don't rule out asking for help
If you're really struggling with your feelings, and/or you think they may be a result of your own experiences growing up, think about having some counselling.