"Fine," Amanda gave in, "You can play with us. As long as you don't tell Dad."
"Of course I won't," Flora promised, before running up to her sister and giving her a hug.
"Can we go back inside?" Kelsey asked.
"Sure," Flora said excitedly, "We'll go up to your room Amanda!"
The two 18 year old girls, and the younger 14 year old walked up the stairs to Amanda's bedroom, before closing and locking the door behind them to make sure there weren't any interruptions. The three of them sat in a circle on the floor with their legs crossed.
"I think it's my turn for revenge on you Amanda," Kelsey commented, trying to scare her friend while still covering, "However, the question of how to get my revenge is a bit tricky. I know! I dare you to..."
"Wait a second!" Flora interrupted Kelsey, "I have a good idea of how to dare my sister. I have lived with her all my life, and I know exactly what she hates most."
"Well," Kelsey said, uncertain how to proceed, "Just whisper it in my ear and I might choose to do that, or maybe make a mixture of our two ideas."
"Okay," Flora eagerly said as she moved her body towards Kelsey's and began to whisper in her ear.
"I have made up my mind," Kelsey said, "I didn't like your sister's idea much more than my own, so I shall use my own instead. I dare you, to take off your shirt, and leave it off until we have woken up again. So you must sleep without a shirt on, and you aren't aloud to cover your chest with your hands."
"What?" Amanda asked, "You can't be serious? You know I don't sleep with a bra on! Oh you are going to pay big time for that one."
Suddenly Flora was quite interested in seeing her sister's bare chest, and said, "A dare is a dare Amanda, you have to do it!"
"Fine, I'll do it," Amanda surrendered as unbuttoned her shirt and took it off for Kelsey's and Flora's eyes to see her big bouncy boobs.
Kelsey's and Flora's eyes were glues to the bare chest of Amanda.
"Wow my big sis has big tits," Flora was half mocking, half in shock.
"Shut up, or I'll make this double dare a lot worse for you two!" Amanda threatened.