I've lost 5 cats, over 17 years. Sometimes, I couldn't even THINK about adding a cat for 18 months. Sometimes, a cat /kitten who needed ME tuned up 5 days later.

Grief is a strange thing. It is different every time. It depends on the relationship you had w/ the departed (pet or human) AND on the stage you are at in your life. No one can tell you when is the right time for you to get another feline, that is a personal decision.

People can remind you to consider: the newbie will be an individual, who wants to be loved for itself. It will not be a replacement, but a new being who enters you life. The personality will be unique, and maybe be completely different. You need to be adding a newbie because it is right for you AND THAT living thing.

As for Clover, in general it is best to add a feline wile she is young. Lik umans, pets are most adaptable when young.

And of course, nothing says you must get a kitten. Shelters are full of young and mature adult cats just wanting a furever home!