Just as the op is entitled to say she feels sad that her babies are growing we bereaved parents are just as entitled to say what a silly sentiment it really is in the harsh reality of some people's lives.
On any thread there are differing opinions just as there are on this thread.
It IS a silly sentiment because your children should grow up. They should experience all the stages.
Some of us know the harrowing reality that some children don't grow up.
Does that mean we are not allowed to have an opinion? Not allowed to say anything?
We say things not to make 'normal' people (those who have not experienced child loss) feel bad, but to gently point out that rather than feeling sad you are lucky to celebrate your children growing.
We know the op did not mean to offend but we are all part of a forum that entitles us all to speak freely.
I am desperately sad that my eldest son died.
I am thrilled that my youngest son is having a chance of life.
The sadness I feel looking back at their childhood is through the eyes of someone knowing one of my children died.
Had he not died I may be whistful for the baby years, but not sad.
There is a way to show empathy to bereaved parents. And there is a way to isolate them further - don't read these threads, etc.
There shouldn't be a them and us. Trust me we feel shit enough without having to defend ourselves.