carriers is you have the option at very first, when you starting off baby facing you. they would have head adjustable harness and as they get bigger, they will also have the options of control on the legs so the baby won't slide out. most carriers also don't fit everybody properly. before you purchase one, it is also recommended you try them out and make sure they fit you properly. also as the baby gets older, you have the option of forward facing them, once they get a little older they like to be curious and seeing everything coming at them instead of go away from them. they still give 