Pam (The Hardest Part)

Pam is the mother of Lisa.

History
Pam, Terri, and Ricky were in talk therapy with Sheldon and Violet because their three daughters, Casey, Lisa, and Jamie had made a pact to get pregnant together in high school.

The three daughters also came in to have take therapy together, to try to explain why they'd done it. Casey said she didn't think she should worry about good grades or college when all she wanted was to be a mom, Jamie said it was instant status, and Lisa said babies love you no matter what. There's a lot going on at her house, so her mother can't give them all attention all the time.

Ricky came in late to their joint session. She'd told Jamie she needed to pick up her brother, but she came back with Violet's book, saying Violet wasn't the right therapist for their daughters. She took Jamie and left.

Sheldon and Violet took Casey and Lisa to tour the hospital. Casey and Lisa by that point had read Violet's book and made several comments about it. Violet started to fight back, but Casey started having serious abdominal pain and bleeding. She was rushed in for an emergency c-section. Lisa watched as Casey's baby was delivered and said it wasn't what she expected and left.

Lisa went to see Violet and said she'd read her whole book. She said seeing Casey's baby being born made her feel like she'd screwed up. She said it wasn't fair to her mother to put another child on her as she already had three. She needed her mom and didn't want to be more of a burden. Lisa said she wasn't sure if she wanted to keep the baby, but she needed help talking to her mom about it. Violet suggested they talk to her together.

Familial
She is a single mother with three kids. Her daughter, Lisa, didn't want to be any more of a burden to her mother by adding a child of her own onto her responsibilities.