There really ought to be some kind of imperative to post the ages of one's DC on threads like these and the circumstances in which one is parenting them. It'll help you sift: you need to be asking parents who are careworn and threadbare from parenting teens through EAs and going off the rails, and parents of sick or disabled children, and parents of children with SEN. Asking someone who really wanted children and who is now parenting a squishy toddler and a precocious 6-year old with no additional needs, and who both sleep well, is neither here nor there. Of course they're going to say it is peak satisfaction.
If I'd parented a couple of DC like DC1, I'd tell you it was the loveliest thing I'd ever done (while crediting my evidently awesome mothering for DC's sooper-dooperness) and highly recommended parenthood, with the caveat to bear the changing climate in mind.
Instead, I feel compelled to tell you about DC2 whose care needs and their impact on every aspect of my life have brought me to some very lonely and dark places of exhaustion, self-doubt, frustration, isolation, hopelessness, fear for the future, depletion of assets and resources and loss of faith in the systems and institutions which are supposed to support families like mine. This is the story shared by most of the parents of older children with disabilities I know. We love our DC fiercely. And it is singularly the hardest thing, despite having a decent support network and parenting in relatively comfortable circumstances.
There really is no telling what parenthood will bring: love, reward and a validation of your efforts in the world or a tempering like no other and a call to grow beyond what you imagined possible.
And let's not forget the favourite truism of many teens, growing up with and without serious challenges: "I didn't ask to be born, did I?!"