I had two older cats ( both boys), and then got offered 2 kittens (1 girl 1 boy).
1 older cat and the male kitten ended up running away and never saw them again but that is not why i am posted lol.
When we first got the kittens, the 2 older ones would like run at them as in to attack then stop just in time, sort of warning them, they all ended up good friends, infact would all sleep together etc...very sweet.
My mum has a cat who is about 15, and even when younger no way would he EVER entertain another cat in his house, i took my kitten to my mums once thinking oh they be fine, mums cat will KNOW it is only a baby and certainly won't hurt it!!!
Yeh right! mums cat lunged at the kitten, and the kitten definately lost one of its lives lol, just managed to stop mums cat in time, think he would have ripped the kitten to shreds tbh.
So depends on the cat really, also older cats are more grumpy and can't be bothered iykwim, they just want a easy life, not some young lively nipper hanging off thier ear/tail/whatever!