Neopets, Nintendogs, My Singing Monsters, Tamagotchi are my best among others. Though I know that all the virtual pet games are really very good and fun to play.
I love that pick . Furby is definitely another fantastic addition to what I've got up there. Its evolving personality and emotions make it so endearing.
 
I love that pick . Furby is definitely another fantastic addition to what I've got up there. Its evolving personality and emotions make it so endearing.
I remember my sisters owning Furbies when we were kids. They had a couple of them at one point.

It’s interesting to see how much they’ve evolved since the 90’s.
 
I love that pick . Furby is definitely another fantastic addition to what I've got up there. Its evolving personality and emotions make it so endearing.
I didn't have an interest then on Furby maybe because of the name but I was happy when I got a glimpse of it and what it have. Virtual pets are really fun.
 
I'm surprised nobody mentioned P.F. Magic's Petz! That series spoiled me so bad for interactivity and AI that Nintendogs *bored* me as a child. Pretty robust breeding/genetics system, too.

Here an interview one of the fans had with one of the programmers in 2018, it's really interesting.

And here's a video of in-game footage from Petz II:


Most people these days play Petz 4 or Petz 5, but Petz II uses basically the same character rendering as the later games.