I'm not related, I just enjoy looking.
By now you may have found a great deal more information. There is so much out there on this family.
Herbert Wilmer Bullard WWI draft b 9 Apr 1888 Sioux Falls SD
living in Minnehaha SD w/ wife and child
SD Marriage Index H W. Bullard married Nellie Ostrander 1 Jan 1915 Nellie age 23 lives Spencer, McCook Co SD H.W. age 27 Sioux Fall SD
1900 census Ramsey, McCook SD Herbert Bullard b Apr 1889 (probably wrong) is with
father L. A. b Oct 1858 NY parents NY
wife Nancy b. July 1856 Indiana f. PA m Virginia
Bertha age 13 b. Dec 1884 b. SD
Walter age 10 Mar 1886 b. SD
One interesting fact is that Bertha May Bullard married Ross Blaine Ryder. Could be where Blaine's name came from.
Bertha and Ross had a son Gordon Eldridge Ryder b. 17 Dec 1902. Gordon died Apr 1977 Seattle, King WA. Bertha died 8 Jul 1925 Codington SD.
In WW II draft regist. Herbert Wilmer Bullard b 9 Apr 1888 Sioux Falls SD is in Vandenburgh Indiana with wife Madgie and employed by the WPA.
In the 1910 census Nellie Ostrander age 17 is in Wheeler Lyon Iowa with father John W. age 53 b. NY, mother "Orilla" b. MN and siblings Alta age 14, Pearl age 11, Jesse age 20, Alvard 2. John is a hotel proprietor.
The 1900 census Lloyd Dikinson Iowa gives their birthdates.
John Feb 1857
"Orila" Jan 1859
Clara B. Jul 1887
Jessie L Feb 1890
Nellie May 1892
Altie L Apr 1895
Pearlie May 1898
In 1920 John A Ostrander is in Spencer McCook SD with his second wife cora M., Jess L. 29, and Arvord 12.
SD Death Index shows "Orllia" Ostrander died 14 May 1918.
Jesse L. Ostrander d 4 June 1938 McCook Co.
This only scratches the surface. In addition there are several online trees that include Nellie and her family.
You did the hard work by getting the adoption records. The rest will be easier. Have fun.