Going to be difficult to track the daughters.
Eve Alda has a facebook page, and based on her 55th birthday celebration video (posted to You Tube by her son, Jake), she married James M. Coffey, whom she met in Cancun, and had 2 children, both boys, Scott Alda Coffey (who is an actor) and Jake Alda Coffey (who appears to be studying screenwriting and just relocated to Burbank, California (Facebook sources).
Beatrice Alda is an actress, but not a lot of information is available on her. It appears she may be married to a Jennifer Brooke, but I can't confirm. I suspect this is the same Jennifer Brooke who is producer/director/writer for one film from Forever Films, but again, it's hard to tell.
Elizabeth Alda is an actress, and even less on her. No family. And little information past her 1986 appearance in Night of the Creeps.
Unfortunately, none of this is very helpful in finding a link.