HI, I am the OP. We lost our mom in the 1960s. Showing my age I guess.

Nope, didn't receive therapy then. IN fact, we only have gotten therapy as adults. I'd say that we definitely didn't know how to handle the loss as kids and did carry it into adulthood.
I don't think people were that on top of therapy for kids in the 1960s. We have both received therapy as adults.
My father was a wreck back then, basically. I do agree that my sister developed a hard outer shell as protection against the upheaval in our lives. We are both productive though and I haven't had a hard time adjusting to adulthood, as mentioned by the prevous poster. I've held the same job for years, have a graduate degree, mortgage and married a very stable, good man. I also have a daughter.
I have never told off my sister when she puts me down because I realize how important 'family' is. I just let her shoot her missiles at me and then get off the phone feeling awful and feeling sad that this is someone I cannot go to in times of hurt or conflict. She just isn't there.
Thanks!