The two pop stars appear to have been glued to their TV screens with the rest of the nation this month, watching the likes of Luisa Zissman, Dappy, Lee Ryan and Jim take part in the popular Channel 5 reality competition.
And with the Celebrity Big Brother final just around the corner, it is clear that Niall and Louis have a firm favourite.
Earlier today (28 January), Niall expressed his excitement about the upcoming episode of the show by tweeting: "Lookin forward to #CBB tonight! Jim Davidson is a legend, and it was great when his wife and daughter came into the house!!"
And his sentiments were echoed by bandmate Louis a couple of days before, as he tweeted: "I've made a decision .... Jim to win ! #CBB"
Louis later added: "Jim's wife what a ledge !! #CBB"
So it seems the two singers are fans of Jim's entire family!
Despite having a pretty packed schedule, the One Direction boys are clearly making time to keep up with their favourite show. At least we're not the only ones who are hooked!
And Louis has been giving his opinion on a couple of the other CBB housemates too, branding Luisa as "awful" and Lee as "the most deluded man ever to grace the Earth".
The 22-year-old 1D member also tweeted: "Lee always embraces his 'G' side while talking to Dappy ! Maybe they'll leave the house and form a gang ? #CBB"
We have to say, we would quite like to see that happen!
Luisa, Dappy and Jim have each made it to tomorrow night's Celebrity Big Brother final, along with Sam Faiers, Ollie Locke and Casey Batchelor.
The penultimate episode will air tonight at 9pm on Channel 5.
Who are you backing to win CBB this year? Let us know below, as the best comment from across the website each week wins £50!
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