I agree with Sandy in the fact that nothing really prepares you for the changes parenting brings! However, it's a huge responsibility to mentor a child throughout their formative years to become a loving, responsible and productive adult, and it's a job that's sadly sometimes under-rated. I think that it's crucial for parents to set a good example for their children, so if someone is still behaving like an immature kid themselves or has some unhealthy habits they're not prepared to give up, perhaps they're not quite ready yet. Parenting can be very tiring at times too, so if we're not healthy (physically, mentally or emotionally), it may be advisable to work on our own issues and resolve those first before we add extra complexity to our lives. A loving, committed and supportive partner is a big help too, although other family members can also provide extra support when needed.