From the Hollywood Reporter:

The live-action project, “Grumpy Cat’s Worst Christmas Ever,” will bring “fun and irreverence” to the network, says Lifetime exec Arturo Interian.
…
Lifetime is casting the voice of Grumpy for the live-action project, which will shoot this summer. The cable network said the movie, which Interian describes as “a little Home Alone and a little Die Hard,” would also feature cameos from other famous Internet memes.
Does anything else need to be said about this? I didn’t think so.

- Courtesy Lifetime

Aslong as he plays a piano, all will be well.
No one hates it more than grumpy cat himself. Herself? What the hell is grumpy cat?
Grumpy cat is a she.
And she obviously thinks you suck, just look at her.
What Trollkien said. Hairballs yes, hairy balls no.
Voice ideas for Tarder: Katherine Turner, Laverne Cox, Carrie Fischer, Lindsay Lohan.