We like the name [name]Katherine[/name], but my brother’s wife’s name is [name]Katie[/name]. We’re trying to find a different nickname if we decide to use [name]Katherine[/name].
[name]Kate[/name]
[name]Kitty[/name]
What else?
[name]Kay[/name]
[name]Rina[/name]
[name]Kat[/name]
[name]Kathy[/name]
[name]Katie[/name]
My name is [name]Kathryn[/name], I like the idea of being ‘ryn’ but Im 20 now so [name]Kate[/name] has stuck.
I like [name]Kat[/name], [name]Kit[/name], [name]Katya[/name], [name]Caddie[/name], and [name]Rin[/name]. There’s also [name]Kari[/name], Kath, Rinny, [name]Rinna[/name], or [name]Katha[/name].
Here are all the ones I can think of:
[name]Kat[/name]
[name]Kattie[/name]
[name]Kate[/name]
[name]Katie[/name]
[name]Kit[/name]
[name]Kitty[/name]
[name]Rin[/name]
Rinnie
[name]Rina[/name]
[name]Katrina[/name]
[name]Kathy[/name]
I have a friend [name]Katherine[/name] who just goes by Kath. Would nn Kather be stupid? Because I think it sounds kind of cool.
The only one that I can think of that hasn’t been mentioned is [name]Kiki[/name]. I may be able to brainstorm some more if I know the MN? 
Want to repeat – [name]KITTY[/name]
Also, [name]Cricket[/name] and [name]Kay[/name]
And [name]Katinka[/name], [name]Tinka[/name], Tink
I saw irisrose suggested [name]Caddie[/name]… We use this nickname for our baby [name]Catherine[/name]. So I like that one… We also use [name]Cat[/name] but [name]Caddie[/name] is sweet for a little one, a good alternative to [name]Katie[/name]. I hardly hear it used.