Kids, gotta love em! Congratulations!
In regard to speakers... What I did was get heavy stands (filled with sand) with small monitor speakers & attached to them with an ample amount of blue tack. That worked well.
In regard to children... My oldest child was the problem. He is 32 now & well behaved, but he wasn't growing up. Naturally curious & always looking for fun. At one point, he took ALL of my albums out of their cases & played with them on the living room floor. That was expensive but was solved by sorting out the bad ones & putting the rest of them up out of his reach. He was my listening buddy (& still loves music to this day). I bought a new power amp when he was about 6 & "we" hooked it up. Listened to it for about 10 seconds & it became unstable to the point of smoke not only coming from the amp itself but from the speaker drivers as well. After I scrambled to unplug everything, he looked at me & said in a calm voice "we won't be listening for a while". It was funny really. FWIW audio isn't the only thing you need to be concerned about... This same child took a box of "oxy pads" to my brand new cars finish to clean it.
Now about cats and girls... My daughter (a year younger than him) loved cats so we got her one. That beautiful little animal got behind my rig & literally chewed all the interconnect wires off at the rca connectors. In regard to audio, she wasn't much of a problem herself until she got older. My straight A daughter had a party at the house (go figure) & one of her friends tipped over one of my speakers on to my turntable. Damaged both. It was naturally my fault though because the speaker was to close to the walkway.
Have fun!