Marsha, the aunt is very judgemental of others and harsh in judgement of them.
People like this are the reasons why people like Nancy end up hiding what they consider "dirt" about their family from relations. Marsha judged Adam. She said herself it couldn't have been Ryan, as he was too well educated. What an ignorant thing to say!
As if her God fearing children are any better. Who is she to judge?
Maybe had she had any humility at all or compassion in her heart, Nancy would have felt she could share her personal problems about caring for Adam and how out of control he was getting with Marsha?

They all this would have been avoided.

Yet no, Nancy was afraid of others judging her and didn't share details with Marsha. Only very few.
She also claimed she was the only one who could help Adam everytime the school tried to help.

God forbid Adam was getting special help, Marsha would think the family subhuman.

We need to live in a more compassionate world, not a world where people are constantly looking down on others due to disabilities. Did your God teach you that?