This thread has been referred to in the thread at
https://www.rootschat.com/forum/index.php?topic=819642.0 - rather than letting that one veer too far into Harry Morris, I'm replying here.
No-one has mentioned it yet, but I suggest you have a look at Lancashire BMD -
http://www.lancashirebmd.org.uk/Not all counties have a site like this, but where they do, they sometimes give you more information than the GRO does. This is especially true for marriages, where you get the spouse's full name and the place of marriage.
So I've just done a marriage search for Harry Morris in the years 1900-1932 (whole county), which produced 68 results in total. Of these, I thought 7 appeared to be in the Jewish faith: these include Harry's marriage in 1932 to Ethel Cohen, so there would be 6 earlier ones, any one of which could be his.
The information from this site should help you to look into possible children, using surname plus mother's maiden name - FreeBMD is probably the place to check first, but you might as well check Lancashire BMD too. And having the spouses' first names might also help you to find the death of his first wife.
One further thought - the number of marriages for a Harry Morris on that site suggests it wasn't a particularly uncommon name - and this was just Lancashire - so I'd be very cautious about assuming yours was one of the ones found in prison records unless you can find further evidence.