And so it was for dad Dan Urbano – until he decided to put an end to it by setting his two children what he thought was an impossible task that would silence their nagging.
He told seven-year-old Remi and his toddler sister, Evelyn, that if they could get 1,000 Facebook Likes on their plea for a cat - he would give in and get pet for the family in Newton, Massachusetts.
But he had no idea about the power of Facebook and that his children's cute post would go viral, amassing nearly 120,000 likes and over 100,000 shares from across the globe.
Mum Marisa helped her two children, write their wish on a white board which they held up for the world to see.
It read: "Hey Facebook! My sister and I really want a CAT. Our papa promises we can get one if we can get 1,000 Likes. Please Like this picture. Thank you!"
Then Marisa added her own appeal: "Dan thinks there is NO way we can do this. I say there is. Help us out. If you can't like, shares. Shares count too! Thanks so much everyone!!"
It took just one day for the post to go viral, with Likes coming in across Europe and Asia from people they didn't even know.
Dan said: "I knew I was screwed when within an hour we had 400 likes and Marisa was still trying to figure out how to make the picture 'public' once she figured that out that's when things started going nuts."
Once the children lived up to their part of the deal, their dad had no choice but cave in and get them a feline friend.
They decided to choose a cat from the Ellen M Gifford Cat Shelter in Brighton, Massachusetts and chose a green-eyed tabby, they selected over the weekend, and they named her 'Hairietta L. Pawturr.'
They said her middle initial stands for 'Likes,' to pay tribute to the online method that helped the youngsters secure their pet cat.
"Thank you to all the kind souls out there who rooted for our kids and taught us all a few lessons about how much kindness there really is in the world and how powerful social networks are," Marisa posted.
"We never intended to get this much attention, but are so happy to have put smiles on some faces and most importantly to have saved a life. Thank you to the Ellen Gifford Cat Shelter for helping us find our newest family member, they are a wonderful organization and were so kind to our family. Hooray for happy endings!"