No, Catholic Doctrine allows for Jews and Muslims to go to heaven, and basically the followers of any other religion. There could even be a loophole for atheists if they, through no fault of their own, had not come to know God but tried to lead a good life.
From here, the Vatican II Council announced:
Could be kinda awkward, especially if one of the heavenly attributes is cross-species communication. Imagine running into a pig who provided the bacon for a BLT that you decided you just didn’t like enough to finish.
So the Pope is ant-plant! Figures.
The Pope never knew my cocker spaniel.
Tanks dere, Mr. Popeguy.
**Colibri **has already come in with the official Church position…but I always figured it worked something like this:
Even if you’re an atheist in life, you get one last shot when you die, and you appear before God for judgement. If you look at Him and say “Aw fuck…I thought you were just a fairy tale! Ummm…my bad…”, that’s enough to fulfill the ‘believer’ requirement. On the other hand, if you stare directly into His face and still say “Nope, sorry, you’re not real”…well, then you’re on your own.
They will do what the people there are doing. Pointing down and laughing at the non-believers. 
Heaven’s kind of like the dope.
Just don’t be a jerk and you’ll be welcome.
When I was going to Catholic grade school, I sometimes wished I had been born into a non-Catholic family, because it seemed so much easier to get to heaven. All I’d have had to do was lead a good life, in blissful ignorance of all the Catholic rules. If you’re a Catholic, one impure thought, having communion without the proper fast, or holding back an egregious sin at confession (something horrible, like arguing with brother) could get you a one way ticket to Hell, or so I thought at the time.
Heaven is being on Earth with your dogs/cats/pets. In my case, numerous dogs, a few horses, a few cats. Couple of rodent types. Crickets as a kid, and a toad, and a snake. Pope Francis is IMO the MOST real prelate the Church has had since the Boy Himself. What a gift to mankind. A non-Catholic who went briefly to Catholic grade school, I’m sure some of the nuns and priests are spinning in their graves (habit era). My lapsed Catholic Irish Grandda would smile quietly and return to Mass 
Surely, not serpents!
Not automatically, but heaven is potentially open to all according to Ctholic doctrine. The only way to be guaranteed to be refused entrance is to know that god exists and nevertheless consciously reject him. Atheists don’t fit this bill, since we don’t believe he exists.
And why should any special efforts be required to enter heaven, anyway? This is just petty.
Well to does say (traditionally) the lion will lay with the lamb. No indication that snacking is involved.
There are plenty of potential angels who would argue that it wouldn’t be heaven if “they” were allowed in.
What is a leech going to do in Heaven? 
For many fundamentalists, it’s even easier than that. You just have to accept Christ as your personal savior. After that, you can do whatever you want. (Of course, if you’ve truly accepted Christ into your heart, you wouldn’t want to act like Dr. Evil, or even Hugh Hefner.)
Only, as it turns out, that acceptance/belief part isn’t necessarily that easy. I tried for years, and failed. Sigh.
The lion may lay down with the lamb. But the lamb won’t get much sleep.
-Woody Allen
Anyone whoever said that has never been to hell. You can’t even get your iPod to work there!
Also, that sentiment is great if you’re Lucifer, but the average Joe Sinner doesn’t* get *to rule in hell. His choices are serve in heaven or burn in hell.
Was this supposed to be “Catholic” or “Cthulhic”? 
But Homer Simpson says that some dogs go to Doggie Hell:
Blondi (Hitler’s dog)
Checkers (Nixon’s dog)
“One of the Lassies is in there, too. The mean one! The one who mauled Timmy!”