I have three little ones all within 22 mos. of eachother, so I speak from experience on this topic. Have a pair of B&W CDM-1NTs in our family room as mains. . .here's what I did.
I bought a a pair of very heavy steel four-column stands and filled each with 100 lbs. of lead shot--net weight is now 135 lbs each (not including speakers). That pretty much takes care of the "topple" factor. Plus, it gave me the excuse to go a little OCD on mass loading.
Next, I carefully drilled into the bottoms of the speakers and installed threaded inserts. Yes, I know that this will "kill" the resale value, but I don't plan on parting with these terrific monitors. I also drilled a hole completely through the top plate of the stand--now I can insert a allen head bolt up through this hole in the top plate and into the threaded insert in the bottom of the speaker. So it's not going anwhere. And the speaker is firmly coupled to the stand (I used some Blu-Tack to protect finish of speaker and for constrained layer damping. . .uh oh, more OCD behavior. . time for meds).
Next, I bought some extra long zip ties and secured the grilles by going all the way around the perimeter of the speaker/grille at the top and bottom. . .so that took care of that. Ugly? Yes. Effective? Yes. Temporary? Yes. I made sure the smooth surface of the zip tie was up against the cabinet walls, as I didn't want to chance that those little 'teeth' on the ties would mar the finish. . .plus, I read somewhere the little teeth will tame room resonance but you have to be sure to have an odd number of them exposed. . .or maybe I just dreamed that part.
Finally, I enjoyed my speakers and waited until my kids grew up enough to no longer show an interest in them and would also listen to our gentle admonitions. Zip ties are now gone and kids are way cool about respecting the gear. Plus, they LOVE music which is the outcome I'd hoped for.