(Jane Upp confirms that it's Ben Madison with Ethel, and behind Ben's right shoulder is Rosalinda. But Barbara Cox thinks that the woman might be Josephine, rather than Rosalinda, and that the man to the right of her (between Ben and Ethel) could be Joe Hamilton the ball player (and her husband). Barbara also thinks that the couple on the left might be Rosalinda and her husband Fred Riccomi (although given their age, I suspect it might be the couple to the right...)).
(As a side note, Rosalinda Olcese Riccomi is buried in Hornitos, where she was born (in Dec 1894, daughter of Frank Olcese and Emelia Gagliardo Olcese). Her husband Fred (Alfred) Riccomi is also buried there, as is her sister, Josephine Olcese Hamilton Stephens (born 1900) and her husband Joseph Hamilton).