Small kids ... playful and high flying cats ... all pose similar problems to the both their own health and the health of your speakers.
The NHT's are good choices because they are sealed box designs and can be wall mounted or placed on a shelf or placed inside a bookcase. The Classic 3's are excellent speakers. Depending on the size of your room, the Classic 2's may work out as well. I used NHT SB2's on shelves inside of a bookcase (15 x 10 x 8.5 sized room) for a number of years with both NAD solid state and Prima Luna tube equipment and loved the sound. You will lose some of the soundstaging, but that is about it.
In general, speakers that are sealed box or front ported will work for you. Rear ported speakers will only work, if they are designed to be near a rear wall and/or wall mounted. Which brings me to two other speakers to consider.
The Rega R1 is a real sleeper of a speaker ($550). I use the previous generation (Ara) in two of my systems; one set on top of a bookcase (solid state receiver), the other inside of a bookcase (tube amp) and the sound is very good. Warm with a good sense of detail, a decent amount of bass for a very small speaker, non-fatiguing listening.
The other is the Polk LSi7 ($600, if you look around on the net). There is an incredible amount of technology packed into this speaker. It has been very well reviewed. It can be wall mounted.
I wouldn't trade my cats in for anything, but Buster currently, Ruby in her heyday and Maddie from yesteryear terrorized many a speaker set-up.
Listening to Netrebko and Le Nozze di Figaro on my Rega Aras, Prima Luna Prologue 2, and Rega Apollo as I write this.
Regards, Rich
