Laugh it off.

You walk up to Kayla, putting a hand on her shoulder. She freezes as you turn her to look at you.
"I'm....I...." she's embarrassed and terrified...."I don't..."
"Kayla, relax. I'm not going to do anything. You're not in trouble." you try to be reassuring.
"It's just... whenever Frank would give me something, a gift or...you know...there was always...an understanding... I guess old habits die hard."
You shudder inwardly. What a sleazeball.
"Kayla, don't worry. I'm not Frank. I'll transfer the funds to your account tonight. Don't give it a second thought. And don't worry about this. It's not a big deal." You laugh, and she laughs nervously along with you.
"Oh......Ok..." she giggles, clearly still flustered, but she's regaining her composure. "Thanks for everything. You should get home before Jenna flips out. I know she must be fuming about you coming in. I'll send that fruit basket!"
"Why don't you bring it over, when you come for dinner tonight?"
Kayla looks dumbfounded. "Wha...I'm coming to your house for dinner, now?"
"What, did you have plans?"
"Netflix and a bottle of wine were my plans. Won't that make more trouble with Jenna?"
You shake your head. "It's time we all stopped acting like teenagers. You're a part of my family, strange as that seems, and it's time we all buried our hatchets and had a good time together. I'm making an executive decision."
She smiles broadly. "Ok! I'll bring a big frozen lasagna and a fruit tray or something!"
"Sounds lovely, Kay. See you at 4:00."

You head home, bracing yourself for the argument when you tell Jenna about the invitation, but frankly, you're tired of it. Kayla's not a bad person. She never has been, and it's time for Jenna to grow up.
You pull into the driveway right behind Jenna, and help her with the groceries. Just as you put away the last of it, the twin horns of two vehicles sound as they pull into your driveway.