"Gemma, Mother's murder is a blight on this family. It would be scandalous if the true facts were known." He stares at me. "Mother died of cholera," he says emphatically, as if even he believes the lie now. (3.47)
Tom is trying desperately to keep the family out of gossip, to make sure they stay in good standing in society—it ensures he and Gemma will both be able to marry into a lot of money. Funny how Gemma doesn't care about this though, and instead wants nothing to do with the lie.
"Yes, I am, as you put it, quite all right." I could laugh, it's such a lie—I am most certainly not all right. (3.46)
Gemma lies to Tom about being okay after her mother's death—though since she is answering his cryptic question about whether she is a virgin or not, perhaps this isn't a lie. While Tom isn't lying in his question, communication would be a whole lot clearer if he'd just say what he means.
That's what living in their world is—a big lie. An illusion where everyone looks the other way and pretends that nothing unpleasant exists at all, no goblins of the dark, no ghosts of the soul. (3.46)
This is a pretty mature and insightful thought Gemma has, and it shows how much she thinks about life and truth and who she wants to be.
"I say, Gemma, are you all right?" Tom is truly concerned.
I'm going mad, Tom. Help me.
"I was simply in a hurry." The sound coming out of my mouth is a cross between a laugh and a howl, like the sound a madwoman would make. (3.78-80)
Have you ever covered up what was really going on inside because you thought the other person couldn't understand? Gemma does this a lot. It is technically lying, but is it wrong to keep some things private?
"Father's no addict. Not Father," he says, as if he means to convince a jury. "He'll be fine now that he's back in England." (3.53)
Good 'ol Tom is never at a loss for a lie, whether he's lying to himself or his sister about the nature of their family. It seems as though he needs to have these lies in place to keep feeling good about himself and to feel confident in society.
"Ann, darling," I say, copying Pippa's chummy tone from earlier. Everyone seems surprised to hear me speak, no one more surprised than I am at the moment. "Don't be modest. Tell Miss Moore the truth." […]
"Yes," I say, hoping I can make this up as I go along.
"The truth—"… (6.54-57)
Oh no she didn't… Gemma comes back with an awesome lie to rival the Torture Twins. We don't feel bad at all about it either because she does it to get poor Ann out of hot water.
"My ring! What have you done with my ring?" The scarves fly open. Ann backs out with the other girls bearing down on her, Felicity pointing a finger accusingly. "Where is it? Tell me this instant!"
"I d-d-don't have it. I d-d-didn't d-do anything." (6.33-34)
Here Felicity and her cruel crew lie in order to punish Ann for talking about how wicked they are to Gemma. They mean to get her expelled for stealing, and this kind of lie is just mean.
"You take that back!" Felicity says through her teeth.
"I won't!" Pippa is crying. "You know it's true. Your mother is a courtesan and a consort. She left your father for an artist. She ran away to France to be with him."
"It isn't true!"
"It is! She ran away and left you behind." (16.53-56)
When situations are painful and confusing, sometimes it is easier to lie to ourselves than to face the truth.
"Why not? Are your feelings hurt that you didn't feel what the rest of us did?"
"Don't be ridiculous," I snort, a sound that seems to accompany my lies, which is most unfortunate. I'm on the road to becoming a snorting fool these days. (16.4-5)
Lying ain't pretty, but it seems a little unfair that Gemma's started snorting every time she lies. After all, sometimes she has to lie to protect pretty legit secrets.
"What if I just used a bit of magic, just enough to help Father and my friends with it—nothing else?"
She takes me by the shoulders like a child. "Gemma, you must listen to me. Do not take the magic out of the realms. Promise me."
"Yes, fine!" I say, tearing out of her grasp. (25.92-94)
This isn't a lie yet, and it doesn't become one until later on when Gemma breaks her promise and betrays her mother—but we think Gemma shows that she isn't serious about her promise here, and chooses to lie to her mother to get her to stop. Classic teen move.