Howard Family Members in Sherlock Holmes

I have never seen the boy actor who portrayed Antoine in "The Deadly Prophecy" identified, but I have little doubt that it was Steven Howard, Ronald Howard's son. I would love to have that confirmed. The baby used in two episodes, "The Baker Street Nursemaids" and "The Jolly Hangman" had to be his daughter Fenella, but I haven't found any confirmation of that, either. Mrs. Ferguson, the replacement housekeeper in "The Singing Violin" bore such a startling resemblance to our charming Mr. Holmes, that I believe she may have been his Aunt Irene Howard. I'm also convinced that little sister, Leslie Ruth, AKA Doodie, attended the Suffragette meeting in
"The Careless Suffragette", stating 'I've never heard of a bomb shop". If anyone can confirm, or refute, my suppositions, please let me know.