A couple of things:
1. I think this is Elizabeth's mother's birth entry:
CATHERINE LAMB WILSON Birth: 01 JAN 1859 Kelso, Roxburgh, Scotland
Parents: Father: ROBERT WILSON Mother: JANE ARCHIBALD
This may explain why you are getting both names Lamb/Wilson coming up.
2. If the marriage cert for Elizabeth is difficult to read due to faintness of writing and legibility, you should contact SP and request a paper copy which can make a huge difference in terms of reading the entry.
3. There are no details I can see (birth/marriage/death) on SP for a Henry Mid*m*ss (picking up on all variants!). Variants for Henry are really only Harry never Thomas. If this is one of the areas that is hard to read from the image on line, hopefully the paper cert. will confirm the correct name....which I think from the what I have found is probably Thomas.
4. You have an entry of marriage between a Thomas and a Catherine. I have found their 1881 Census entry. They have had a daughter Elizabeth, also mother in law Jane Archilbald (mother of Catherine Lamb Wilson above?) is living with them:
Thomas MIDDLEMASS, 31, head, b. Yetholm, Roxburgh, Scotland, Agri. labourer
Catherine, 22, wife, b. Kelso, Roxburgh, Scotland
Andrew, 4, b. Kelso, Roxburgh, Scotland
Janet, 3, b. Roxburgh, Roxburgh, Scotland
Elizabeth, 1, b. Roxburgh, Roxburgh, Scotland
Jane ARCHIBALD, 61, married, Crailing, Roxburgh, Scotland
Dwelling: Trows, Roxburgh, Roxburgh
So everything fits, just the issue of Thomas v. Henry which hopefully is due to illegibility of the writing on the image you have.
Regards.
Monica