Try having kids, building a life with someone is easy mode until you throw multiple children into the mix. It's the final milestone of the human metamorphosis and it's a challenge.
Been there, done that. Bought one of the kids an axolotl after lots of pester-power and boatloads of "I promise I'll look after it, feed it and clean its tank every day".
So it's come to pass that now I look after it, and every time there's a new "Dad, can I have a XXX as a pet?" I can say "Well, you haven't looked after the axolotl". And since they can live for 25 years, there is some method to my madness ;)