You didn't mention dates your family were at High Street, so I calculated a year that might be of interest based on possible Index records and public trees. If the details I have are correct then the person you mentioned would have been about 15 at the time of this listing.
Thom's 1944, High street
From Nicholas St. to Corn Market
North side - east to west
1. & 2. Fitzgerald & Carey, draper
3. vacant
4. tenements
5. W.P. Byrne,timber & slater merch.
6. L. Bannon, provisions
7. John Rush, pork butchers
8. Thomas Keogh, hairdresser
9. tenements
9a. Thos. Kenny, general smith
10-11. Thos. Victory, prov. merch.
12. (ruins)
13. Michael Doherty, grocer, tea, wine & spirit merch
...jct. Schoolhouse lane....
14-16. St. Audeon's RC Church & Presbytry
(Rev. T.W. O'Ryan, M. Geraghty, John Kavangh)
17. O'Connor & Co., wholesale clothier
18. G.S.B. Mack, fancy goods
19. P. McLoughlin, boot maker
20. tenements
21. M. Conlon, grocer
22. Miss. Kay, confectioner
23. T. & S. Curran, bedding manuf.
24. tenements
.... jct. Cornmarket & St. Audeon's Park....
South side - west to east
25. J.J. Weafer, stationery & tobaccos
26. tenements
27. M. Tyrell, newsagent & tobacconist
Town Sub-Post Office, Money Order & Savings Bank Office
Miss Mary Tyrell sub-postmistress
28. Mark Deering, picture frame maker
29. vacant
30. J. Brady, hairdresser
31. (ruins)
32. J. Gannon
33. St. Vincent de Paul Penny Savings Bank
34. (rebuilding)
35. D.J. Monaghan, grocery & prov.
36. M. & E. Musgrave, wholesale tea merch.
37. J.F. Lidwell, watchmaker
38-42. (empty space)
(no. 43 not listed)
44. tenements
45. vacant
46. O'Shea, watchmaker.
47-48. John Hendrix, undertaker, hearse & job coach prop.
49. Wm. Wilby, patent belt. manuf., mill & factory furnisher
50. J.E. Mullins, reg. plasterer & elect. eng.
51-52. Leinster Manuf. Co., shirt manuf.
(G.P. Kelso, J. Nesbitt & W.E.T. Richardson)
....jct. Angel Court......
53. S.H. Danker, furniture dlr.
....jct. Angel Alley......
54. Peter Kenna
55. Michael Powell, purveyor
56. Restaurant
57. J. Kennedy, wine and spirit merch.