My family has a connection with Brighowgate Childrens` Home and also the Workhouse ( which was in Scartho Road Grimsby ) although slightly earlier that your relative.
If children under 5 were admitted to the Workhouse with their mother, they stayed there until 5 and then were moved upto Brighowgate.
There are some photos which are available to view, I did this at NELincs Archives, but I think some are closed.
Also, there are at least 2 booklets about these establishments; one which was written by Sadie Beal whose husband was the Master of the Workhouse and another one I think written by possibly Philip Grundy. Both contain some photos. I will see if I`ve got them.
Again, I`m not sure, it`s years since I visited those archives, but I think the last entry in the admittance book was 1927, which I was told had the 100 year closure rule, so that is well past now.