Though I don't have any pets now but I had few when I was a school going kid till my engg second year! Had a puppy, then a cat, then fishes, and then a hen!
Puppy - I found this cute little puppy while playing cricket near my friends house, this was when I was in 4th standard. Named it tommy. One find day when I started for my school in my dad's scooter it loosened up the chain and ran behind the scooter I was standing in front so couldn't hear it's barking. When I came back from school that day I found my puppy missing...
Cat - Nancy was it's name. My aunt presented me nancy when I was in 6th standard. It was a white cat with small golden yellow spot on it's right side. It used sleep in my bed during winter season and mom used to get irritated at that sight. Due to snake bite it died when we went out for a movie.
Fishes - I fished out few fishes with a net (taare zameen par.. :P) from a small pond at my grandmas town. Brought them to my home in bottle from there and was in a process of building an aquarium for them but one day my dad overfed those fishes and they all died... hmm..
Hen - I bought this as chick for 15 bucks when I was in engg second year. I fed it nicely we used play and then it had a friend, cat. Cat used to ambush where this used to go. And then one day it ran off from home and it never returned back. I went out and searched whole evening in the streets. After a month it came back but it didn't recognise me, hmm..so I let it go where ever it wanted to...