Good Morning Ray, 

Thank you for contacting the U of M Extension Service. 

Please click on the following link from the U of M Extension Yard and Garden website about creeping bellflower: https://extension.umn.edu/weeds/creeping-bellflower

Please scroll down for information about control. It is a pesky plant!

I used my plant identification app on the small plant that you sent a photo of. My app indicated that this plant is a green ash. I am wondering if the tree in the corner of your third photo is an ash tree? The tree helicopters may be germinating in your lawn.  In the third photo of your lawn, the way the plants are scattered in your lawn, it does not appear to act like creeping bellflower.  If they are tree seedlings, I feel they will die after repeated mowings. 

If you let one of the plants get bigger and take another photo, I'd be happy to attempt to identify it again. 

Good Luck!