Stockton adopted in michigan

my grandmother birth name is bonnie stockton and was adopted when she was 2 years old.her birthday is september 20,1939 and she was born and adopted in michigan.she is 1 of 5 or 6 children.if anybody know anything about her birth parents or her siblings.please reply or message me.any help would be great. and her adopted are thelma and martin klaver.we believe bonnie was her birth name.