You posted this message some time ago and so I wonder if you will read this.
Robert Romer was my great great grandfather and so I can help you with some information about him.
Our branch of the family came over to England in 1688 when a Wolfgang Rhomer, military engineer and architect came to England with William of Orange.
I realise I am slightly unsure about who was Robert Romer's father but I think it was one of John Romer's sons.There are a number of John Romers, I am referring to the John Romer who was an adult family man in the 1830s when a portrait of him with his family was exhibited in the Royal Academy.
John Romer's children included Frank, a composer, Robert, a popular actor, Emma, an opera singer and Helen, also a singer.I think your research has conflated Robert the actor who was this Robert's uncle with him, since I do not believe he ever acted.I believe that Robert's father was Frank (the composer).
Robert Romer was a brilliant mathematician and lawyer.He was "Senior Wrangler" at his college at Cambridge, Trinity Hall(this is a mathematics prize).He went on to be mathematics professor at Queen's College, Cork before reading for the Bar and becoming a barrister.He would have been knighted upon becoming a High Court Judge.He then went on to become a Lord Justice of Appeal in 1899, that is he was a judge in the second highest appellate court in England (the Court of Appeal).
He married his first cousin, Betty, daughter of Helen (his aunt the singer) and Mark Lemon, who was the first editor and a founder of "Punch" magazine, a very popular magazine in its time.
One of his children was my great grandfather, Mark, who also became a barrister.He too was a High Court Judge, then a Lord Justice of Appeal, and then was made a Lord of Appeal in Ordinary.This means he was a judge in the highest appellate court in England, the House of Lords (this was in the 1940s).
One of Robert's other children was Nellie who married Frederick (Freddie) Maugham, who ultimately became Lord Chancellor (the most senior judge in England).Freddie Maugham (or Viscount Maugham) was also the father of Somerset and Robin Maugham, both authors, Somerset better known than Robin.
Another was Sir Cecil Romer, Deputy Chief of the Imperial General Staff in the 1930s.
One of Mark's sons, Charles, my grandfather was also a barrister and he was in the Court of Appeal in around the late 50s/early 60s.
I hope this is of some use to you.If I discover I am wrong and that Frank Romer was not his father I will post another message.