I am answering for myself and as a "cat person". I lost the last of my geriatric kitties within several of each other back in 2000 and 2003. We had them for 16 and 17 years. I was out looking at shelters within days and brought home a pair of sibling kittens, Emily and Eliot. They were in no way a replacement for the pets that were gone - I just can't imagine my home without the company of cats - each unique and different. My closest bond with a kitty was RB Bert who died at age 17 and there will NEVER be another like him. But I will always have more kitties as they need me. Having kittens in my home brought back allot of energy and joy that was missing as the last of my geriatrics passed away - and that lifelong bond came to a close. It was like beginning a cycle over again to me. But a replacement - never.
By the way - we are bringing home another pair of seven week old kittens on the 3rd of October They are the babies of a stray mamma taken in by PT'er Kimlovescats in Tennessee.