When you buy your child their first guitar, there are some important attributes to consider. Obviously you want to ensure that the instrument is the correct size for your child. Many models are too big for children and will inhibit their ability to reach the proper tabs and fingerings.
The next thing to consider is price. Since this is their first instrument, it is probably wise to simply invest in cheap kids guitars so that they have something to cut their teeth on. Just because the price isn’t high doesn’t mean that you have to skimp on quality; there are many excellent models available that don’t carry an excessive price tag.