Grace Annette Duggar shares a middle name with Michelle Annette Ruark Duggar. Also all of the Ms were inspired by Michelle. Michael James Duggar is named after Mike Keller and Jim Bob.
I'm missed that you posted the same thing. MacKynzie, Felicity, Addison (Joe and Kendra), and Bella all share middle names with their mother. Israel and Samuel Dillard both have middle names from Derick's side of the family.
Abbie's middle name is Grace.
Maryella's name was inspired by Grandma Mary. Mason's middle name is also Garrett for Garrett Ruark.