Congratulations, Grandma. You certainly have been blessed.
Now get busy and make these lucky children their own quilts.
If they're old enough to pick colors, that's nice. Or you could
show them some colors and ask them to pick one they like.
Put their (new) names on each quilt, and keep telling them
how lucky YOU are to have such lovely grandchildren.
I've heard horror stories of grandparents who refuse to admit
such adopted kids are "real" ones. Sad, they don't know or even
care that they are missing the love of an innocent child.