Why are children represented as inessential in some Buddhist text? There are multiple question related to this already asked, but none of the response or question address as to why children are presented in Buddhist text as inessential, such as these:


  … That is not a strong fetter, the wise say, which is made of iron,
  wood or hemp. But the infatuation and longing for jewels and
  ornaments, children and wives — that, they say, is a far stronger
  fetter, which pulls one downward and, though seemingly loose, is hard
  to remove…


again


  … Ten children I bore from this physical heap. Then weak from that,
  aged, I went to a nun. She taught me the Dhamma


and again  


  …. Those with children    grieve because of their children. Those with
  cattle grieve because of their cows. A person's grief comes from
  acquisitions, since a person with no acquisitions doesn't grieve…


again What the Buddha said to Visakha when she express her wish to have as many children &amp; grandchildren. 


  “those who have a hundred dear ones have a hundred sufferings”


and many more can be listed.

With such representation, how do lay Buddhists reconcile have children ask skillful?
Such texts should be read in context: written for and by the Sangha - and mostly for and by male-sangha, though you found one quote that sounds like a tired grandmother. 

Buddhism is really a dual religion. The religion for lay-people is very practical: attend to your duties and avoid wrong-doing. That includes taking care of any partner and children. Traditionally things like meditation were limited to the Sangha, and a minority in there as well. 

If you want to become a monk or nun, obviously children are an obstacle as long as they're young. And women do - especially when there is no good medical help - suffer physically from childbirth. Without proper medical attention women die in childbirth in alarming numbers. Women who survived that and grew to an age where they were free to become nuns (very much a minority at any time in Buddhist history) would be encouraged to meditate on topics that helped them let go of their attachment to their children and focus also on the limitations of the body that bore them. No wonder one writes:


  … Ten children I bore from this physical heap. Then weak from that, aged, I went to a nun. She taught me the Dhamma


The Buddha himself walked away from his wife and son - which is hardly a good example to follow. The only mitigating circumstance was that his father was rich and quite capable of taking care of them. 

As lay people we should read such texts within their context: written by monks, for monks. They're not written for lay people. Lay people did not have access to texts and most of the texts that survived don't portray even nuns very well.