1910 United States Federal Census
Name: William H Ingmire
Age in 1910: 55
Estimated birth year: abt 1855
Birthplace: Ohio
Relation to Head of House: Head
Father's Birth Place: United States of America
Mother's Birth Place: United States of America
Spouse's name: Ada L
Home in 1910: Allison, Garfield, Oklahoma
Marital Status: Married
Race: White
Gender: Male
Household Members: Name Age
William H Ingmire 55
Ada L Ingmire 36
Ross J Ingmire 24
Earl W Ingmire 18
Floyd Ingmire 12
Elmar Ingmire 10
Goldie Ingmire 8
Toeddie Ingmire 5
Isome Ingmire 4
Lillie B Ingmire 3
Guy Ingmire 4/12

1920 United States Federal Census
Name: William Ingmire
Home in 1920: Grant, Garfield, Oklahoma
Age: 66
Estimated birth year: abt 1854
Birthplace: Ohio
Relation to Head of House: Self (Head)
Spouse's name: Ada L
Father's Birth Place: Maryland
Mother's Birth Place: Maryland
Marital Status: Married
Race: White
Sex: Male
Home owned: Rent
Able to read: Yes
Able to Write: Yes
Household Members: Name Age
William Ingmire 66
Ada L Ingmire 42
Elmer Ingmire 18
Goldie Ingmire 17
Tedsy Ingmire 15
Ira I Ingmire 14
Guy Ingmire 12
Ethel Ingmire 8
Forrest Ingmire 5 [5 6/12]
Roy Ingmire 3 [3 4/12]
Dortha Ingmire 0 [6/12]

1930 United States Federal Census
Name: William D Ingmire
Home in 1930: Blaine, Garfield, Oklahoma
Age: 75
Estimated birth year: abt 1855
Birthplace: Ohio
Relation to Head of House: Head
Spouse's name: Ada L
Race: White
Household Members: Name Age
William D Ingmire 75
Ada L Ingmire 55
Elmer Ingmire 28
Islam L Ingmire 23
Guy Ingmire 19
Forest Ingmire 14
Roy Ingmire 13
Dorothy Ingmire 10

William H. Ingmire married 1st Julia A. Bond on 15 Feb 1880 as recorded in Marriage Book C400 and most of the children you have listed for he and Ada are by his first marriage to Julia A. Bond.

You can check the 1800 census and find William and Julia Ingmire alone without children and then the 1900 census and see that William is widowed as Julia's death is 1897 as so stated on her grave marker.

The known children will be shown as is in the 1900 census.
Mary Ethel Ingmire
Ross J. Ingmire
Thomas A. Ingmire
Charles H. Ingmire
William E. Ingmire
Harry E. Ingmire
Floyd B. Ingmire

The 1910 census also shows that the marriage of Ada and William is the 2nd for both and that they have been married 10 years. Apparently they married shortly after the 1900 census was taken. The census would also appear that the two have merged their families with children from his first marriage shown.