I am looking for living descendants/relatives of:

Leslie William Johnson b 23 Sept 1894 Gainsborough Lincolnshire
to William Johnson b ~1857 Staffordshire Cradley Heath (Asst Magistrates Clerk in 1911 @Gainsborough)
and Charlotte Sarah b ~ 1871 "Oxford, Oxford" (in 1911 married 18 years, 5 children - all still alive)

Siblings at 1911:
Stanley Merry Johnson b~1896,
Gladys Mary Johnson b~1899,
Frederick Gordon Johnson b~1902,
Marjory Johnson b~1905
(all born Gainsborough Registration District)

Address (1911): 23 Morton Terrace Gainsborough, Gainsborough, Lincolnshire
Address (1901): Same - details broadly consistent

His parents marriage is most probably:
William Johnson m Charlotte Sarah Merry Q4 1893 Headington RD vol 3a page 1297
(Headington is on the outskirts of Oxford, Charlotte's birth place and her second son is named Stanley Merry)

Leslie William Johnson, served and survived the First World War
Enlistment details (1915):
Home address: The Elms, Morton Terrace, Gainsborough
Occupation: Student at Sheffield
Date of Birth: 23 Sept 1894
British Born
Single
Father: William Johnson

He served with the York and Lancaster Regiment initially the 11th, then the 14th (2nd Barnsley Pals) and then I believe the 1/4th (Hallamshire)
Release with effect from 3.4.19
Grant rank of Captain on relinguishing commission
Acting Captain for 6 months, 3 weeks, 1 day

Awarded the Military Cross
T./Lt. (A./Capt.) Leslie William Johnson, York & Lanc. R.
For conspicuous gallantry and devotion to duty when in command of a support company. He formed his company up in the direction of the enemy attack, and held on to his position until the whole of the troops in front had been withdrawn. He set a splendid example of courage and determination.
Gazette Publication date: 13 September 1918 Supplement: 30901 Page: 10972

His medals index card correspondence address was:
71 Yew Tree Lane
South Yardley
Birmingham

(There is another Leslie William Johnson born in Yardley in 1904 (per 1911 Census) to Charles William and Emma Johnson. However he would have been too young to serve in WW1. This however may be a family link).

His brother, presumably Stanley Merry Johnson, was a prisoner of war at one stage.

Any help in tracing descendants of him or his siblings would be very welcome.