Hello and welcome! >w<
I'm only 15 and have never housed a newt or any exotic pet before other than our pet ball python Monty but I was planning on housing a Firebelly Newt or some kind of newt as such and did months of research on just how to take care of it, but it turned up that an Axolotl would be a better exotic pet for me, so I know a bit about both but no experience with them.
The California newt is cute and relatively general to care for with no large speed bumps in any point in it's life but it's quite toxic and might be a bad choice for a household with a 2 year old. There is a few stories of wandering 5 year olds somehow ingesting the newt and dying from it, although I'm not saying your 2 year old is stupid enough to eat a pet newt.
The Firebelly Newt has a toxic gland on it's head that constantly leaks into the water so water changes would have to be frequent but subtle as to not change the conditions vastly different and shock it's systems. The gland is indeed toxic and irritating to human skin, but not fatal and would not cause any harm. The only irritant effect that would come from it would be handling it with a cut or sore and getting the water into a cut or sore or open area such as the eyes. They also don't do well being handled, so maybe a more friendly choice would be better in case your child would want to handle it.
The Axolotl is adorable, easy to care for and very friendly. They do not need or even want a land area, they can be housed happily by itself in a 10 gallon tank although they get lonely and often stop eating if by themselves, so I recommend getting more than one, two are happy in a 20 gallon tank and up. They have a wide diet, you can feed them daphnia, brine shrimp, bloodworms, blackworms, earth worms are the least messy and most fun to feed them with, various smaller fish...They cannot be kept in a tank with other tankmates because their gills are very pretty and attractive and any other tank mate will eat their gills and nip at their feet and end up killing them, and if the tankmate is smaller, the axolotl will simply eat it. If you would like to contact someone with lots of experience with axies I'd recommend the user Bellabelloo. To my knowledge she is a moderator and in fact has bred her axies so she has knowledge and experience from egg to old axie.
There are other newts I have not done research on but I know can be kept as pets, such as the Marbled Newt, Great Crested Newt as well as other crested newts, Eastern and Western Newts, salamanders might be good for what you're looking for, the Long Tailed Salamander is interesting and quite cute and fun to watch walk about with it's loooong tail.
I would not recommend listening to pet store pamphlets about the care of any exotic animal such as snakes, turtles, fish, newts, salamanders or relatively anything other than cats, dogs and birds! I have heard many many stories of exotic animals being kept in pet stores in very poor care because the pet store managers, employees and care takers have no idea what they're doing! One story is of a certain red crab species available for pet ownership (I do believe it was a red crayfish, beautiful creatures) and the pet store had given a man a pamphlet. He had adopted 3 different crab and they died within 6 days of the initial purchase and he looked up online why this was happening and did near to the exact opposite of what the pamphlet said, bought another crab, and it lived for ten years! If you are puzzled about something about any newt or salamander I strongly recommend asking the Caudata community instead of a pet store or question;answer website such as Yahoo! Answers. I've asked several newt-related questions on Yahoo! Answers as well as Axie questions and found the information to be severely false!
I wish you the best of luck with your new pet(s) and hope I helped you at least a little!
Welcome to the forum!
