The 'Best Song Ever' star uploaded a sweet snap of himself holding his young nephew Theo on Monday morning (11 November), adding the caption: "Last time I saw this little man he was four weeks old! He is the best baby ever."
Little Theo is the son of Niall's brother Greg and his sister-in-law Denise.
Niall's cute picture clearly went down a treat with 1D fans as it was retweeted nearly 25,000 times in three hours and generated responses like "be the father of my children" and "GDSHFKLFABOO."
No, we don't know what that means either but we reckon it's good!
While some of us head home to our parents' home for some rest, relaxation and an escape from the craziness of our everyday lives, poor old Niall found that being a member of 1D doesn't equate to peace anywhere.
He attended little Theo's christening in his Mullingar, Ireland hometown over the weekend, only to be mobbed by fans and photographers eager for a glimpse of the heartthrob.
Niall, who is the baby's godfather, was surrounded by fans as he tried to drive away from the church. He was also mobbed while out for a jog the following day.
It seems Niall might want a little peace and quiet as he took to Twitter to plea for a bit of space. "Haven't seen my family in 4 months! Would be soo grateful if I could spend some quality time with them! Appreciate your respect!"
If anyone deserves a bit of downtime it's Niall. You don't need to be a 1D fan to know how hard they work travelling all over the world and always with a smile on their face when they meet fans.
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