I thought this but then I went and looked at what the statements actually said. They could absolutely have just condemed their sister or given more generic "we will always miss mum and dad" quotes, or as one said ""To me this situation is quite literally a living nightmare from which I will never wake up...The haunting thoughts of [whether] my parents suffered, if they were taunted," but they specifically act as though they were incredibly close, which doesn't make any sense.
""Our mum was kind, caring and thoughtful. Mum delighted in her grandchildren."
How can someone "delight" in their grandchildren if they haven't seen or even spoken to them (e.g. on facetime) in more than 4 years, when presumably they live in the same country?
"Child two" says they feel "sick to my core" every day.
"We have been cruelly robbed of more loving memories and bonds with our mum and dad for years to come," they add.
"How dare Virginia rob us of that life?
Again - the dad was quite ill, you'd think if you were that into making loving memories you would have attempted to visit at some point in four years?
Her uncle (mother's brother) said "There are precious times with Lois and John I will miss out on because of the wicked act of their own daughter."
Again, they can't be that precious if you went half a decade without trying to make those 'precious times' happen!
The quote from child 3 is interesting:
"Your lies about our parents' actions and their whereabouts made out as if they didn’t value seeing us," they wrote.
"You have left a hole in my heart forever and a piece of me died with them the day you took them from us."
It provides some explanations as in she was probably making excuses via texts if they did offer to meet up/visit - but this can only go so far. Any normally close family would start seeing red flags if you'd previously been in frequent contact with your parents and then it suddenly stopped.
To go for years, including Christmas, birthdays etc. with never seeing, or even speaking to your parents directly (other than, it seems only one (faked) phone call, to one of the sisters - which is also weird, my sister doesn't sound anything like my mother!) - is not a close family. Which is fine, they are under no obligation to spill the private details of their relationships to the world, but just give generic statements in that case, don't give misleading statements suggesting you were far closer than you were.