Hi Marlene,
My relation to the Ehret family is a very sideways collateral one.

It starts here:
Carol Phyllis Schmid was the daughter of Charles Philip Schmid & Florence Montague Trautman. Florence Trautman was the daughter of Ralph Trautman & Mary E. Blampey. Mary E. Blampey was the SISTER of Maria Blampey who was married to my gr gr granduncle: William Munn.
Now, Carol Schmid was married to William Ottman, the son of William Ottman & Madeline EHRET. Madeline EHRET was the daughter of George EHRET, the brewer, & Anna Hasslocher.

So, this line is through marriage to me; no direct relation. It interests me though because these folks were somewhat well known and industrious, prob. sort of upper class (compared to me anyhow) and I've been able to find information about them. For instance, 2 of my Munn relations in Mass. were given the middle names of Trautman and Blampey; which this research all helped me figure out where those names came from. Florence also had an aunt named Charlotte Montague Blampey and I have yet to figure out where the name Montague came from. This is how I ended up researching the "in laws", etc!
If you google George Ehret brewery you can find some history of his life and business. I wonder if Frank Haas started out working for Ehret?
Also, I am looking at MRS. George Ehret's obit. from Oct. 30, 1899 (NY Time Archives), which says she was Anna Hasslocher, but it also says she was the sister of the late Mgr. HAASlocher, the rector of the American College at Rome. It also lists their 9 children: Frank, George, & Louis Ehret, Mrs. Anna von Zedlitz-Leipe of Berlin, Mrs. Ernst Stangen, Mrs. E. M. Burghard, Mrs. Charles Donahue, and Madeline & Elsie Ehret.
I wonder if it's possible that your Frank Haas was related to George Ehret's wife, Anna Hasslocher and perhaps the name had been shortened to HAAS? Maybe he was her nephew?
I've found an obit from 1903 for a Frederick Haas who established a brewery, but it doesn't give any family info. Also, from NY Times Archives.

I don't know if this is helpful, but hopefully it is.

Lisa