The pair were presenting a segment on the daytime show about guide ponies, when things got a bit mucky.
One of the ponies, which are specially trained to help blind people, took an immediate shine to Holly, who struggled to keep a straight face as it got up close to the presenter.
But then Phillip asked trainer Katy Smith about the differences between guide dogs and guide ponies, saying: “A dog is unlikely to poo on the kitchen floor.”
And with impeccable timing, one of the ponies did just that, all over the studio floor.
The sight of the pony doing its business reduced Holly to a giggling wreck - and most of the viewers at home...
We know it doesn’t take much to make Holly and Phil giggle.
Last month, the prospect of “tasting Fearne Cotton’s cupcakes” really seemed to tickle them.
The pair were trailing an item with the TV presenter-turned baker, when Phil mentioned they would be sampling some of her culinary delights later in the show.
And while we get that “Fearne Cotton’s cupcakes” vaguely sounds like an innuendo (at a push), the pair found it hilarious - with Holly collapsing on the floor in fits.
Watch Holly lose it as Monet the pony does his biz in the clip above.