Claws instead of Key: and the discovery!

Mommy couldn't hear their mews and the four kitties were locked out of their own house!
After a few minutes of frantic chaos and meowes, they finally calmed down and it was Ash who came up with the idea. "Why haven't we thought of this before?" she mewed, "We'll just let ourselves right in."
"But  how?" questioned Sherlock, "did you forget we don't have the key?"
"Don't have the key?" Ash repeated, "hello-- did you forget what our claws are for?"
"Oh yeah" mewed Sherlock, letting it all sink in. "I get it."
It wasn't long before Ash unlocked the back door and they all pawed inside.
"Home at last!" they mewed. Ash sprawled onto the couch and took a catnap, Sherlock settled into his cat tree, Traveler got out his favorite cat nip toy and Sasha brought out the meow mix.
"We're home!" they mewed "We are definatley home!"
But it wasn't long before they stopped their relaxation and partying and realized something was different.
"Mommy is gone!" they mewed, "and there's a bunch of strange cardboard boxes filling the house!"